https://armhub.dev The modern reference for ARM development — architecture, peripherals, RTOSes, toolchains, vendors, and real-world system designs. en Fri, 15 May 2026 04:48:57 GMT https://armhub.dev/docs/architecture/aapcs/ https://armhub.dev/docs/architecture/aapcs/ Wed, 13 May 2026 00:00:00 GMT How ARM functions pass arguments, return values, preserve registers, align the stack, and interact with FPU / vector state. Covers AAPCS32, AAPCS64, and the variations for VFP and Helium. architecture https://armhub.dev/docs/peripherals/timers-advanced/ https://armhub.dev/docs/peripherals/timers-advanced/ Wed, 13 May 2026 00:00:00 GMT TIM1 and TIM8 on STM32 — complementary PWM outputs, dead-time generator, break input, repetition counter, encoder and Hall sensor modes, and the master-slave synchronization that drives multi-timer motor-control pipelines. peripherals https://armhub.dev/docs/peripherals/dma-advanced/ https://armhub.dev/docs/peripherals/dma-advanced/ Wed, 13 May 2026 00:00:00 GMT Beyond the classic stream-based DMA — master DMAs that initiate transfers across the bus matrix, 2D blending engines for graphics, linked-list scatter-gather, and cache coherency on Cortex-M7 systems. peripherals https://armhub.dev/docs/vendors/ambiq-apollo4/ https://armhub.dev/docs/vendors/ambiq-apollo4/ Wed, 13 May 2026 00:00:00 GMT Apollo4 family — Cortex-M4F at 192 MHz, 2 MB flash, MIPI-DSI display, 2D GPU, BLE 5.1 on Plus variants, sub-microamp deep sleep. The silicon behind the modern AMOLED smartwatch. vendors https://armhub.dev/docs/vendors/ambiq-apollo5/ https://armhub.dev/docs/vendors/ambiq-apollo5/ Wed, 13 May 2026 00:00:00 GMT Apollo510 — first commercial Cortex-M55 with Helium MVE for wearables, dedicated NPU for on-device AI, 4 MB MRAM, MIPI-DSI and MIPI-CSI. The platform for the AI smartwatch generation. vendors https://armhub.dev/docs/vendors/ambiq/ https://armhub.dev/docs/vendors/ambiq/ Wed, 13 May 2026 00:00:00 GMT Ambiq's sub-threshold voltage SPOT technology — the silicon behind every multi-week-battery-life smartwatch and hearing aid. Apollo family from Apollo1 to Apollo510, software stack, why wearables design teams choose it. vendors https://armhub.dev/docs/tools/semihosting/ https://armhub.dev/docs/tools/semihosting/ Wed, 13 May 2026 00:00:00 GMT How semihosting lets a target Cortex-M call into the debug host for printf, file IO, and time — the SVC 0xAB trap, the operation table, host implementations, the latency cost, and when to use it instead of a UART. tools https://armhub.dev/docs/architecture/armv6m/ https://armhub.dev/docs/architecture/armv6m/ Wed, 13 May 2026 00:00:00 GMT The minimal M-profile ISA — what's in ARMv6-M (Cortex-M0, M0+, M1), what's missing compared to v7-M, and the design decisions that drop the gate count to under 12k while still running C code. architecture https://armhub.dev/docs/cortex-a/isa-compare/ https://armhub.dev/docs/cortex-a/isa-compare/ Wed, 13 May 2026 00:00:00 GMT How the Cortex-A instruction set evolved across three architecture generations — AArch32 vs AArch64, register file expansion, the death of conditional execution, NEON to SVE2, and what MTE/PAC/BTI mean for compile-target choices. cortex-a https://armhub.dev/docs/architecture/armv7m/ https://armhub.dev/docs/architecture/armv7m/ Wed, 13 May 2026 00:00:00 GMT The mainstream M-profile ISA — full Thumb-2, IT blocks, LDREX/STREX, optional MPU and FPU, DSP extensions, bit-banding. The architecture behind Cortex-M3, M4, and M7. architecture https://armhub.dev/docs/cortex-r/isa-compare/ https://armhub.dev/docs/cortex-r/isa-compare/ Wed, 13 May 2026 00:00:00 GMT How the Cortex-R real-time family evolved — R4/R5/R7/R8 on ARMv7-R, the MPU-only memory model, lockstep, V-FIQ, and ARMv8-R's introduction of EL2 hypervisor and (with R82) AArch64 to the real-time domain. cortex-r https://armhub.dev/docs/architecture/armv8m/ https://armhub.dev/docs/architecture/armv8m/ Wed, 13 May 2026 00:00:00 GMT The current M-profile generation — Baseline and Mainline, TrustZone-M security extension, improved MPU, stack-limit registers, and the v8.1-M Helium MVE that lights up Cortex-M55 and M85. architecture https://armhub.dev/docs/architecture/armv8r/ https://armhub.dev/docs/architecture/armv8r/ Wed, 13 May 2026 00:00:00 GMT The real-time R-profile — MPU-based memory protection (no MMU), hypervisor support for real-time virtualization, lockstep, EL0/EL1/EL2 exception levels. Cortex-R52 and the AArch64 R82. architecture https://armhub.dev/docs/vendors/artery-at32f4/ https://armhub.dev/docs/vendors/artery-at32f4/ Wed, 13 May 2026 00:00:00 GMT AT32F403 through AT32F437 — the high-clock M4F mainstream. Pinout-compat with STM32F407, up to 288 MHz, 4 MB flash, CAN-FD. Architectural detail and migration mechanics. vendors https://armhub.dev/docs/vendors/artery-at32m/ https://armhub.dev/docs/vendors/artery-at32m/ Wed, 13 May 2026 00:00:00 GMT AT32MC family — dedicated BLDC, PMSM, stepper, and SRM motor-drive MCUs with high-resolution timers, complementary PWM, dead-time generators, overcurrent comparators, and FOC reference firmware. vendors https://armhub.dev/docs/vendors/artery/ https://armhub.dev/docs/vendors/artery/ Wed, 13 May 2026 00:00:00 GMT Shanghai-based vendor of high-performance Cortex-M4 MCUs targeting STM32F4 replacement at lower cost — 240 MHz clocks, larger flash, AT-Link debug, and aggressive China-market pricing. vendors https://armhub.dev/docs/systems/autosar/ https://armhub.dev/docs/systems/autosar/ Wed, 13 May 2026 00:00:00 GMT AUTOSAR — the automotive software architecture standard. Application layer, RTE, BSW (MCAL, ECU abstraction, services), communication and diagnostics stacks. Adaptive AUTOSAR on Cortex-A with POSIX and ara::com. systems https://armhub.dev/docs/systems/iot-sensor-node/ https://armhub.dev/docs/systems/iot-sensor-node/ Wed, 13 May 2026 00:00:00 GMT Architecting a battery-powered IoT sensor node — Cortex-M0+/M33 plus Sub-GHz or LTE-M radio, sleep budget in microamps, LoRaWAN / NB-IoT / BLE mesh / Wi-SUN / Zigbee. OTA, secure provisioning, deep-sleep buffers in RTC backup RAM. systems https://armhub.dev/docs/cortex-a/big-little/ https://armhub.dev/docs/cortex-a/big-little/ Wed, 13 May 2026 00:00:00 GMT ARM's asymmetric multiprocessing — the evolution from big.LITTLE cluster migration through global task scheduling to DynamIQ's mixed-core single-cluster design, with the Linux Energy Aware Scheduler tying it all together. cortex-a https://armhub.dev/docs/programming/bootloaders/ https://armhub.dev/docs/programming/bootloaders/ Wed, 13 May 2026 00:00:00 GMT Bootloader architecture for Cortex-M. ROM vs flash bootloaders, vector-table relocation, dual-bank fail-safe update, signed and encrypted firmware, MCUboot, STM32 system bootloader, USB DFU. programming https://armhub.dev/docs/programming/c-tutorial/ https://armhub.dev/docs/programming/c-tutorial/ Wed, 13 May 2026 00:00:00 GMT A 15-lesson hands-on tutorial taking you from hello world through pointers, memory, the preprocessor, the standard library, and modern C11/17/23. Built for people who already program and want to learn C properly. programming https://armhub.dev/docs/programming/tutorial/ https://armhub.dev/docs/programming/tutorial/ Wed, 13 May 2026 00:00:00 GMT A hands-on 10-lesson tutorial. Set up GCC, blink an LED without HAL, read registers, write a linker script, handle interrupts, decode CFSR/HFSR, build a DMA-driven UART driver — all from scratch. programming https://armhub.dev/docs/programming/cpp-lesson-10-lambdas/ https://armhub.dev/docs/programming/cpp-lesson-10-lambdas/ Wed, 13 May 2026 00:00:00 GMT Lambda syntax, capture by value vs reference, mutable and generic lambdas, init-capture, the anonymous class lambdas desugar to, and the function-pointer decay rule. programming https://armhub.dev/docs/programming/cpp-lesson-11-error-handling/ https://armhub.dev/docs/programming/cpp-lesson-11-error-handling/ Wed, 13 May 2026 00:00:00 GMT Return codes, exceptions, and std::expected (C++23). Exception cost, noexcept, exception safety guarantees, and why most embedded builds use -fno-exceptions. programming https://armhub.dev/docs/programming/cpp-lesson-12-concurrency/ https://armhub.dev/docs/programming/cpp-lesson-12-concurrency/ Wed, 13 May 2026 00:00:00 GMT std::thread, mutex and lock_guard, condition variables, atomics with memory ordering, async/future, jthread, and a lock-free SPSC queue example. programming https://armhub.dev/docs/programming/cpp-lesson-13-modules/ https://armhub.dev/docs/programming/cpp-lesson-13-modules/ Wed, 13 May 2026 00:00:00 GMT Module interface and implementation units, export and import, partitions, header units, compile-time wins, and the current state of compiler and build-system support. programming https://armhub.dev/docs/programming/cpp-lesson-14-modern/ https://armhub.dev/docs/programming/cpp-lesson-14-modern/ Wed, 13 May 2026 00:00:00 GMT A tour of C++23 features that actually change how you write code — std::expected, std::print, stacktrace, deducing this, if consteval, and the C++20 highlights worth catching up on. programming https://armhub.dev/docs/programming/cpp-lesson-15-embedded/ https://armhub.dev/docs/programming/cpp-lesson-15-embedded/ Wed, 13 May 2026 00:00:00 GMT Building a real Cortex-M firmware in C++23. The flag list, the global-constructor fiasco, STL without exceptions, and a small worked driver bringing every previous lesson together. programming https://armhub.dev/docs/programming/cpp-lesson-09-move-semantics/ https://armhub.dev/docs/programming/cpp-lesson-09-move-semantics/ Wed, 13 May 2026 00:00:00 GMT R-value references, move constructors, std::move, the rule of five and the rule of zero, noexcept moves, and why STL containers fall back to copy without it. programming https://armhub.dev/docs/programming/cpp-tutorial/ https://armhub.dev/docs/programming/cpp-tutorial/ Wed, 13 May 2026 00:00:00 GMT A 15-lesson hands-on tutorial taking you through classes, RAII, templates, the STL, smart pointers, move semantics, lambdas, modules, and modern C++23. Built for C programmers and embedded engineers. programming https://armhub.dev/docs/cortex-m/cache-tcm/ https://armhub.dev/docs/cortex-m/cache-tcm/ Wed, 13 May 2026 00:00:00 GMT Cortex-M7/M55/M85 I-cache, D-cache, and tightly-coupled memory. Line size, write-back vs write-through, invalidate/clean, DMA coherency, ITCM/DTCM bring-up. cortex-m https://armhub.dev/docs/peripherals/can-fd/ https://armhub.dev/docs/peripherals/can-fd/ Wed, 13 May 2026 00:00:00 GMT CAN with Flexible Data-rate — the second-generation CAN protocol with up to 64-byte payloads and accelerated data-phase bit rates. How the bit timing works, the new frame layout, hardware controllers, and what changes for software. peripherals https://armhub.dev/docs/programming/cmsis-dsp/ https://armhub.dev/docs/programming/cmsis-dsp/ Wed, 13 May 2026 00:00:00 GMT The ARM CMSIS-DSP library — vector math, FIR/IIR filters, FFT, matrix ops, statistics, and transforms. Q-format fixed-point, performance on M0/M4F/M7/M55 Helium, and practical audio and PID examples. programming https://armhub.dev/docs/cortex-m/coresight/ https://armhub.dev/docs/cortex-m/coresight/ Wed, 13 May 2026 00:00:00 GMT TPIU, ETM, ITM, DWT, FPB, AHB-AP, DAP, SWJ-DP. How a debug probe reaches the core, ROM tables, DWT cycle counting accuracy, the JTAG vs SWD trade-off. cortex-m https://armhub.dev/docs/cortex-m/architecture-compare/ https://armhub.dev/docs/cortex-m/architecture-compare/ Wed, 13 May 2026 00:00:00 GMT Every Cortex-M core side by side — pipeline depth, DMIPS/MHz, ISA profile, MPU, FPU, cache, TCM, TrustZone, vector ops, and typical silicon clocks. The single reference table. cortex-m https://armhub.dev/docs/cortex-m/m0/ https://armhub.dev/docs/cortex-m/m0/ Wed, 13 May 2026 00:00:00 GMT The smallest, lowest-power Cortex — ARMv6-M, 3-stage von Neumann pipeline, Thumb-only ISA, no MPU, no cache. The minimum-viable 32-bit MCU. cortex-m https://armhub.dev/docs/cortex-m/m0plus/ https://armhub.dev/docs/cortex-m/m0plus/ Wed, 13 May 2026 00:00:00 GMT The improved M0 — two-stage pipeline, optional MPU, single-cycle GPIO on some vendors, MTB instruction trace. The default low-end Cortex for new designs. cortex-m https://armhub.dev/docs/cortex-m/m23/ https://armhub.dev/docs/cortex-m/m23/ Wed, 13 May 2026 00:00:00 GMT ARMv8-M Baseline — the M0+ successor with TrustZone-M, improved ISA (divide, compare-and-branch), and an updated MPU. The smallest secure-capable Cortex. cortex-m https://armhub.dev/docs/cortex-m/m33/ https://armhub.dev/docs/cortex-m/m33/ Wed, 13 May 2026 00:00:00 GMT ARMv8-M Mainline — the modern mid-tier Cortex. TrustZone-M, optional FPU and DSP, MPU, 3-stage pipeline. The default pick for new secure IoT and industrial designs. cortex-m https://armhub.dev/docs/cortex-m/m55/ https://armhub.dev/docs/cortex-m/m55/ Wed, 13 May 2026 00:00:00 GMT ARMv8.1-M with Helium (M-profile Vector Extension). Scalar+vector core for ML inference and DSP, optimized for pairing with Ethos-U NPUs. cortex-m https://armhub.dev/docs/cortex-m/m85/ https://armhub.dev/docs/cortex-m/m85/ Wed, 13 May 2026 00:00:00 GMT The highest-performance Cortex-M — ~3.0 CoreMark/MHz, Helium, branch prediction, PAC/BTI security, and the de-facto M7 replacement for new high-performance MCUs. cortex-m https://armhub.dev/docs/cortex-r/interrupts/ https://armhub.dev/docs/cortex-r/interrupts/ Wed, 13 May 2026 00:00:00 GMT How Cortex-R parts handle interrupts — Vectored Interrupt Controller, TI's VIM, GIC on R52, the IRQ vs FIQ distinction, direct vector lookup vs software dispatch, and how it all compares to Cortex-M's NVIC. cortex-r https://armhub.dev/docs/cortex-r/r52-cluster/ https://armhub.dev/docs/cortex-r/r52-cluster/ Wed, 13 May 2026 00:00:00 GMT Split vs lockstep configurations in a Cortex-R52 cluster — up to 4 cores, mix of lockstep pairs and independent cores, inter-core memory bus, L1 cache coherency in split mode, and use in ASIL-D powertrain and brake-by-wire designs. cortex-r https://armhub.dev/docs/architecture/debug/ https://armhub.dev/docs/architecture/debug/ Wed, 13 May 2026 00:00:00 GMT How ARM debug works under the hood — DAP, AHB-AP, JTAG vs SWD, the FPB breakpoint unit, DWT watchpoints, vector catch, CoreSight, ROM tables, and the difference between halting and sampling debug. architecture https://armhub.dev/docs/systems/drone-esc/ https://armhub.dev/docs/systems/drone-esc/ Wed, 13 May 2026 00:00:00 GMT Drone ESC firmware — BLDC commutation (back-EMF zero-cross vs sensored), six-step trapezoidal vs FOC sinusoidal, PWM 16–32 kHz, DShot300/600/1200 digital throttle protocol, bidirectional DShot for RPM telemetry, BLHeli_32 / AM32 / BetaFlight ESC. systems https://armhub.dev/docs/systems/drone-imu/ https://armhub.dev/docs/systems/drone-imu/ Wed, 13 May 2026 00:00:00 GMT MEMS gyro and accelerometer for drones — ICM-42688-P, BMI270, magnetometer and barometer fusion. Complementary filter, Madgwick, Mahony, full EKF. Sample rate 8 kHz, low-pass to 100 Hz, gyro-bias tracking. systems https://armhub.dev/docs/cortex-m/dwt-itm-etm/ https://armhub.dev/docs/cortex-m/dwt-itm-etm/ Wed, 13 May 2026 00:00:00 GMT Debug Watchpoint and Trace, Instrumentation Trace Macrocell, Embedded Trace Macrocell. PC sampling, cycle counting, SWO printf, exception trace, function trace. cortex-m https://armhub.dev/docs/cortex-r/ecc/ https://armhub.dev/docs/cortex-r/ecc/ Wed, 13 May 2026 00:00:00 GMT How Cortex-R parts catch hardware faults — SECDED Hamming on TCMs and caches, parity on bus interfaces, the ESM (Error Signaling Module) in TI TMS570, precise vs imprecise data aborts, and how software-driven error injection drives functional safety tests. cortex-r https://armhub.dev/docs/peripherals/ethernet/ https://armhub.dev/docs/peripherals/ethernet/ Wed, 13 May 2026 00:00:00 GMT The Ethernet peripheral on Cortex-M parts — MAC vs PHY split, MII/RMII/RGMII interfaces, descriptor rings, PTP hardware timestamping, hardware checksum and VLAN offload, and the MDIO bus that configures the PHY. peripherals https://armhub.dev/docs/systems/ev-charger-power/ https://armhub.dev/docs/systems/ev-charger-power/ Wed, 13 May 2026 00:00:00 GMT EV charger power electronics — AC-DC PFC, isolated DC-DC LLC, three-phase rectification for >7 kW, CC/CV control, vehicle communication via Control Pilot PLC (J1772/CCS). Cortex-M role in digital control loops. systems https://armhub.dev/docs/architecture/exclusive-monitors/ https://armhub.dev/docs/architecture/exclusive-monitors/ Wed, 13 May 2026 00:00:00 GMT The atomic primitive that builds every lock on ARM — the LDREX/STREX exclusive monitor. How it works, when it clears, how to layer spinlocks and lock-free counters on top, and the ARMv8.1 CAS instruction that supersedes it on Cortex-A. architecture https://armhub.dev/docs/tools/profiling/ https://armhub.dev/docs/tools/profiling/ Wed, 13 May 2026 00:00:00 GMT Measuring where time goes on Cortex-M — DWT PC sampling, SystemView, Tracealyzer, ETM streaming with J-Trace, and embedded gcov for coverage. When statistical wins, when full trace wins, and how to wire each up. tools https://armhub.dev/docs/cortex-m/fpu/ https://armhub.dev/docs/cortex-m/fpu/ Wed, 13 May 2026 00:00:00 GMT FPv4-SP on M4, FPv5-SP/DP on M7/M33/M85, MVE on M55/M85. Register file, FPSCR, lazy stacking, extended stack frame, CPACR enable, denormal handling. cortex-m https://armhub.dev/docs/tools/formal-methods/ https://armhub.dev/docs/tools/formal-methods/ Wed, 13 May 2026 00:00:00 GMT Mathematical proof of firmware properties — Frama-C with WP and EVA, TLA+ for protocol design, CBMC bounded model checking, Astrée abstract interpretation. When the investment pays off, and how Airbus, SEL, and Amazon use them. tools https://armhub.dev/docs/cortex-a/gic/ https://armhub.dev/docs/cortex-a/gic/ Wed, 13 May 2026 00:00:00 GMT How interrupts are routed on Cortex-A — GICv2 vs v3 vs v4, SGI/PPI/SPI/LPI classes, distributor + redistributor + CPU interface, affinity routing, priority/preemption rules, and the EOI/active-priority stack. cortex-a https://armhub.dev/docs/vendors/gigadevice/ https://armhub.dev/docs/vendors/gigadevice/ Wed, 13 May 2026 00:00:00 GMT Beijing-based MCU vendor shipping Cortex-M0+/M3/M4/M7/M23/M33/R52 parts as pin-and-register-compatible STM32 alternatives with their own peripheral IP and aggressive pricing. vendors https://armhub.dev/docs/vendors/gigadevice-gd32f/ https://armhub.dev/docs/vendors/gigadevice-gd32f/ Wed, 13 May 2026 00:00:00 GMT GD32F1 through GD32F7 — the workhorse Cortex-M3/M4/M7 line. Pin-and-register compatibility with STM32F1/F3/F4/F7, the migration gotchas, and which part to pick for which design. vendors https://armhub.dev/docs/vendors/gigadevice-gd32l/ https://armhub.dev/docs/vendors/gigadevice-gd32l/ Wed, 13 May 2026 00:00:00 GMT GD32L23 and GD32L235 — sub-microamp stop modes, TrustZone-M, LPUART, LPTIM, and the GigaDevice answer to the STM32L0/L4 battery-IoT slot. vendors https://armhub.dev/docs/vendors/gigadevice-gd32w/ https://armhub.dev/docs/vendors/gigadevice-gd32w/ Wed, 13 May 2026 00:00:00 GMT GD32W51x — single-band Wi-Fi 4 plus BLE 5.x on a Cortex-M33 with TrustZone-M. The GigaDevice answer to ESP32 and STM32WB, with HMAC/AES/SHA acceleration. vendors https://armhub.dev/docs/peripherals/gpio-af/ https://armhub.dev/docs/peripherals/gpio-af/ Wed, 13 May 2026 00:00:00 GMT How a single physical pin gets multiplexed between dozens of peripherals — alternate-function tables, output type, slew-rate control, pull resistors, Schmitt input, and the vendor differences between STM32 AF, NXP IOCON, and Nordic GPIOTE. peripherals https://armhub.dev/docs/systems/industrial-gateway/ https://armhub.dev/docs/systems/industrial-gateway/ Wed, 13 May 2026 00:00:00 GMT Industrial edge gateway architecture — Cortex-A application plus Cortex-R5 or PRU real-time. Fieldbus interfaces (Modbus, EtherCAT, PROFINET, IO-Link), TSN, OPC UA server, MQTT to cloud, Linux + containerised apps. systems https://armhub.dev/docs/vendors/aurix/ https://armhub.dev/docs/vendors/aurix/ Wed, 13 May 2026 00:00:00 GMT Infineon AURIX — TriCore-based automotive microcontrollers (NOT ARM), ASIL-D capable lockstep, on-chip HSM, used in EV powertrain inverter control and ADAS sensor fusion. Why an ARM-focused reference covers AURIX, and how it pairs with Cortex cores in modern ECUs. vendors https://armhub.dev/docs/rtos/ipc/ https://armhub.dev/docs/rtos/ipc/ Wed, 13 May 2026 00:00:00 GMT RTOS inter-task communication — semaphores, mutexes, queues, event groups, stream and message buffers, task notifications. Latency, memory cost, and the right tool for each problem. rtos https://armhub.dev/docs/vendors/nvidia-jetson-agx/ https://armhub.dev/docs/vendors/nvidia-jetson-agx/ Wed, 13 May 2026 00:00:00 GMT NVIDIA's top-tier Jetson modules. AGX Orin with 12 Cortex-A78AE cores and 275 TOPS, AGX Thor with Neoverse-derived A720AE and Blackwell GPU at 2000 TOPS for humanoid robotics and autonomous driving development. vendors https://armhub.dev/docs/vendors/nvidia-jetson-orin-nano/ https://armhub.dev/docs/vendors/nvidia-jetson-orin-nano/ Wed, 13 May 2026 00:00:00 GMT NVIDIA Jetson Orin Nano and Orin NX — Cortex-A78AE plus Ampere GPU on a SODIMM module. 20 to 100 TOPS INT8, 5 to 25 W, pin-compatible across the family. Real workloads, nvpmodel power modes, and a comparison with Raspberry Pi 5 plus Hailo-8. vendors https://armhub.dev/docs/programming/c-lesson-01-hello/ https://armhub.dev/docs/programming/c-lesson-01-hello/ Wed, 13 May 2026 00:00:00 GMT The anatomy of a C program, printf and format specifiers, what every gcc flag in the strict build command actually does, exit codes, and why "void main" is wrong. programming https://armhub.dev/docs/programming/cpp-lesson-01-hello/ https://armhub.dev/docs/programming/cpp-lesson-01-hello/ Wed, 13 May 2026 00:00:00 GMT Your first C++ program, std::cout and stream insertion, auto type deduction, nullptr, the using-namespace debate, and a roadmap of the four C++ super-features. programming https://armhub.dev/docs/programming/tutorial-01-toolchain/ https://armhub.dev/docs/programming/tutorial-01-toolchain/ Wed, 13 May 2026 00:00:00 GMT Install arm-none-eabi-gcc, OpenOCD, and GDB. Wire up the ST-Link. Verify the toolchain with a one-line compile and decode every GCC flag. programming https://armhub.dev/docs/rtos/tutorial-01-why-rtos/ https://armhub.dev/docs/rtos/tutorial-01-why-rtos/ Wed, 13 May 2026 00:00:00 GMT Bare-metal superloop vs scheduled tasks. Hard vs soft real-time. The exact list of problems an RTOS solves — and the workloads where it costs more than it gives. rtos https://armhub.dev/docs/programming/c-lesson-10-dynamic-memory/ https://armhub.dev/docs/programming/c-lesson-10-dynamic-memory/ Wed, 13 May 2026 00:00:00 GMT malloc, calloc, realloc, free, the heap, double-free and use-after-free, leaks, valgrind, ownership patterns, a growable vector, and why embedded systems avoid malloc. programming https://armhub.dev/docs/programming/tutorial-10-ringbuffer-dma/ https://armhub.dev/docs/programming/tutorial-10-ringbuffer-dma/ Wed, 13 May 2026 00:00:00 GMT Lock-free SPSC ring buffer with power-of-two sizing. Circular DMA on USART2 RX, half-transfer and transfer-complete interrupts. The driver that ships in production firmware. programming https://armhub.dev/docs/rtos/tutorial-10-tickless-debug/ https://armhub.dev/docs/rtos/tutorial-10-tickless-debug/ Wed, 13 May 2026 00:00:00 GMT Suppress SysTick during idle and save 100×–1000× power. Trace tools — SystemView, Tracealyzer, Ozone. Common bugs and how to find them. Where to go after FreeRTOS. rtos https://armhub.dev/docs/programming/c-lesson-11-preprocessor/ https://armhub.dev/docs/programming/c-lesson-11-preprocessor/ Wed, 13 May 2026 00:00:00 GMT include, define, conditional compilation, function-like macros with parenthesisation, stringification, token pasting, predefined macros, X-macros, _Generic, and when not to use macros. programming https://armhub.dev/docs/programming/c-lesson-12-multi-file/ https://armhub.dev/docs/programming/c-lesson-12-multi-file/ Wed, 13 May 2026 00:00:00 GMT Translation units, the header/source split, extern, the one-definition rule, static linkage, avoiding cyclic includes, building a 5-file project, and a 30-line Makefile. programming https://armhub.dev/docs/programming/c-lesson-13-stdlib/ https://armhub.dev/docs/programming/c-lesson-13-stdlib/ Wed, 13 May 2026 00:00:00 GMT A tour of the headers that matter — stdio, stdlib, string, math, time, assert, errno, limits, stddef, stdint, stdbool, inttypes. File I/O, qsort, bsearch, memcpy vs memmove. programming https://armhub.dev/docs/programming/c-lesson-14-ub/ https://armhub.dev/docs/programming/c-lesson-14-ub/ Wed, 13 May 2026 00:00:00 GMT What UB is and why the compiler is free to do anything. The classic list. Address Sanitizer. The optimisations that exploit UB. The 10 rules to follow in practice. programming https://armhub.dev/docs/programming/c-lesson-15-modern-c/ https://armhub.dev/docs/programming/c-lesson-15-modern-c/ Wed, 13 May 2026 00:00:00 GMT What each revision added — Static_assert, Generic, atomics, nullptr, constexpr, attributes, typeof, BitInt, embed. Which compilers support what and when to use them. programming https://armhub.dev/docs/rtos/tutorial-02-hello-freertos/ https://armhub.dev/docs/rtos/tutorial-02-hello-freertos/ Wed, 13 May 2026 00:00:00 GMT Pull the FreeRTOS kernel from GitHub, wire SysTick/PendSV/SVC, write FreeRTOSConfig.h, build, flash, and watch your first task blink an LED. rtos https://armhub.dev/docs/programming/cpp-lesson-02-references/ https://armhub.dev/docs/programming/cpp-lesson-02-references/ Wed, 13 May 2026 00:00:00 GMT References vs pointers, const T& parameters, namespaces, function overloading, default arguments, and strongly typed enum class — the scaffolding that makes C++ feel different from C. programming https://armhub.dev/docs/programming/c-lesson-02-types/ https://armhub.dev/docs/programming/c-lesson-02-types/ Wed, 13 May 2026 00:00:00 GMT Integer types and the standard's actual guarantees, fixed-width types from stdint.h, floating point, every integer literal form, sizeof, and the implicit-conversion rules that bite. programming https://armhub.dev/docs/programming/tutorial-02-bare-metal/ https://armhub.dev/docs/programming/tutorial-02-bare-metal/ Wed, 13 May 2026 00:00:00 GMT Write main.c, startup.s, and linker.ld from scratch. Build, flash, watch the LED blink. Every line is yours — about 80 lines total. programming https://armhub.dev/docs/programming/cpp-lesson-03-classes/ https://armhub.dev/docs/programming/cpp-lesson-03-classes/ Wed, 13 May 2026 00:00:00 GMT Constructors, destructors, member init lists, the rule of three and five, access control, RAII as the killer feature, explicit, = default, = delete, static members. programming https://armhub.dev/docs/programming/c-lesson-03-expressions/ https://armhub.dev/docs/programming/c-lesson-03-expressions/ Wed, 13 May 2026 00:00:00 GMT Every C operator, the precedence and associativity table, short-circuit evaluation, sequence points, and why a[i] = i++ is undefined behavior. programming https://armhub.dev/docs/programming/tutorial-03-registers/ https://armhub.dev/docs/programming/tutorial-03-registers/ Wed, 13 May 2026 00:00:00 GMT volatile, memory-mapped I/O, peripheral struct types, atomic single-bit writes via BSRR, and the read-modify-write hazards that bite every embedded engineer. programming https://armhub.dev/docs/rtos/tutorial-03-tasks/ https://armhub.dev/docs/rtos/tutorial-03-tasks/ Wed, 13 May 2026 00:00:00 GMT What xTaskCreate actually allocates. Stack sizing with the high-water mark. Priority. Ready/Running/Blocked/Suspended. Observing pre-emption on real silicon. rtos https://armhub.dev/docs/programming/c-lesson-04-control-flow/ https://armhub.dev/docs/programming/c-lesson-04-control-flow/ Wed, 13 May 2026 00:00:00 GMT if, switch, while, do/while, for, break/continue/goto, the case fall-through rule, and the unsigned-loop overflow that catches every engineer at least once. programming https://armhub.dev/docs/programming/cpp-lesson-04-inheritance/ https://armhub.dev/docs/programming/cpp-lesson-04-inheritance/ Wed, 13 May 2026 00:00:00 GMT Single inheritance, virtual functions and the vtable, override and final, virtual destructors, abstract classes, the diamond problem, and when composition beats inheritance. programming https://armhub.dev/docs/programming/tutorial-04-memory-map/ https://armhub.dev/docs/programming/tutorial-04-memory-map/ Wed, 13 May 2026 00:00:00 GMT Walk the Cortex-M memory map — flash, SRAM, peripherals, system region. Decode _etext, _sdata, _edata, _sbss, _ebss. Watch the startup-time .data copy. programming https://armhub.dev/docs/rtos/tutorial-04-semaphores/ https://armhub.dev/docs/rtos/tutorial-04-semaphores/ Wed, 13 May 2026 00:00:00 GMT Binary semaphore for ISR-to-task signalling. Counting semaphore for resource pools. portYIELD_FROM_ISR. The UART-RX-to-parser-task pattern that's in every product. rtos https://armhub.dev/docs/programming/tutorial-05-linker-script/ https://armhub.dev/docs/programming/tutorial-05-linker-script/ Wed, 13 May 2026 00:00:00 GMT Annotate the linker.ld from lesson 2 line-by-line. MEMORY, SECTIONS, AT-load, PROVIDE, ENTRY. Add a bootloader region. Reserve heap and stack. programming https://armhub.dev/docs/programming/c-lesson-05-functions/ https://armhub.dev/docs/programming/c-lesson-05-functions/ Wed, 13 May 2026 00:00:00 GMT Declarations vs definitions, headers and prototypes, pass-by-value (C has nothing else), static and inline, recursion, and the f() vs f(void) trap that bit everyone before C23. programming https://armhub.dev/docs/rtos/tutorial-05-mutex/ https://armhub.dev/docs/rtos/tutorial-05-mutex/ Wed, 13 May 2026 00:00:00 GMT Why a mutex is not a binary semaphore. The Mars Pathfinder story. Recursive vs non-recursive. configMAX_SYSCALL_INTERRUPT_PRIORITY done correctly. rtos https://armhub.dev/docs/programming/cpp-lesson-05-templates/ https://armhub.dev/docs/programming/cpp-lesson-05-templates/ Wed, 13 May 2026 00:00:00 GMT Function and class templates, type deduction, template specialisation, variadic packs, if constexpr, concepts (C++20), and a RingBuffer with N as a template parameter — the zero-overhead polymorphism mechanism. programming https://armhub.dev/docs/programming/c-lesson-06-arrays/ https://armhub.dev/docs/programming/c-lesson-06-arrays/ Wed, 13 May 2026 00:00:00 GMT Array declaration, indexing, the famous array-to-pointer decay, multi-dimensional arrays, designated initializers, VLAs, and a fixed-size circular buffer implementation. programming https://armhub.dev/docs/programming/tutorial-06-interrupts/ https://armhub.dev/docs/programming/tutorial-06-interrupts/ Wed, 13 May 2026 00:00:00 GMT Write a SysTick handler by hand. Configure the timer, define the handler, set NVIC priority, manage volatile shared state, and bracket critical sections with BASEPRI. programming https://armhub.dev/docs/rtos/tutorial-06-queues/ https://armhub.dev/docs/rtos/tutorial-06-queues/ Wed, 13 May 2026 00:00:00 GMT Copy-by-value queues. Producer/consumer. ISR-safe sends. The pointer-vs-copy decision. UART RX parser written the proper way. rtos https://armhub.dev/docs/programming/cpp-lesson-06-stl-containers/ https://armhub.dev/docs/programming/cpp-lesson-06-stl-containers/ Wed, 13 May 2026 00:00:00 GMT std::vector, std::array, std::string with SSO, std::map vs std::unordered_map, std::set, std::deque and std::list, std::span — when to use each, what they cost, and which to avoid on embedded. programming https://armhub.dev/docs/programming/tutorial-07-bit-patterns/ https://armhub.dev/docs/programming/tutorial-07-bit-patterns/ Wed, 13 May 2026 00:00:00 GMT Set, clear, toggle. Multi-bit fields. Sign extension. __builtin_clz, __builtin_popcount, __builtin_ctz. __REV. Saturate-add DSP intrinsics on Cortex-M4F. programming https://armhub.dev/docs/rtos/tutorial-07-events-notifications/ https://armhub.dev/docs/rtos/tutorial-07-events-notifications/ Wed, 13 May 2026 00:00:00 GMT Wait on AND/OR bit patterns for "all subsystems ready" rendezvous. Task notifications — the FreeRTOS fast IPC, ~45× faster than a semaphore. rtos https://armhub.dev/docs/programming/cpp-lesson-07-iterators-algorithms/ https://armhub.dev/docs/programming/cpp-lesson-07-iterators-algorithms/ Wed, 13 May 2026 00:00:00 GMT Iterator categories, range-based for, the std::algorithm header (sort, find, transform, accumulate), and C++20 ranges and views — the operations that work across every STL container. programming https://armhub.dev/docs/programming/c-lesson-07-pointers/ https://armhub.dev/docs/programming/c-lesson-07-pointers/ Wed, 13 May 2026 00:00:00 GMT Addresses, dereference, NULL, pointer arithmetic, const correctness in all three positions, function pointers as first-class values, and a generic sort using a comparator. programming https://armhub.dev/docs/programming/tutorial-08-fixed-point/ https://armhub.dev/docs/programming/tutorial-08-fixed-point/ Wed, 13 May 2026 00:00:00 GMT Q-format primer. Q15 and Q31 multiplication and overflow rules. CMSIS-DSP helpers. A complete Q15 PID controller. When floats are fine on Cortex-M4F. programming https://armhub.dev/docs/programming/cpp-lesson-08-smart-pointers/ https://armhub.dev/docs/programming/cpp-lesson-08-smart-pointers/ Wed, 13 May 2026 00:00:00 GMT std::unique_ptr, std::shared_ptr, std::weak_ptr, std::make_unique, std::make_shared, custom deleters, the owning-vs-non-owning distinction, and why raw new and delete are mostly wrong in modern C++. programming https://armhub.dev/docs/rtos/tutorial-08-streams-timers/ https://armhub.dev/docs/rtos/tutorial-08-streams-timers/ Wed, 13 May 2026 00:00:00 GMT Lock-free byte streams for UART RX. Software timers and the timer daemon task. configTIMER_TASK_PRIORITY pitfalls. The blink-once abstraction. rtos https://armhub.dev/docs/programming/c-lesson-08-strings/ https://armhub.dev/docs/programming/c-lesson-08-strings/ Wed, 13 May 2026 00:00:00 GMT There is no string type in C. NUL termination, the strncpy trap, snprintf as your friend, sscanf pitfalls, why gets is gone, UTF-8, char32_t, and a safe string_copy. programming https://armhub.dev/docs/rtos/tutorial-09-memory/ https://armhub.dev/docs/rtos/tutorial-09-memory/ Wed, 13 May 2026 00:00:00 GMT heap_1 through heap_5 — what each one does and when to pick which. Stack overflow detection. Static allocation for safety-cert builds. rtos https://armhub.dev/docs/programming/tutorial-09-state-machine/ https://armhub.dev/docs/programming/tutorial-09-state-machine/ Wed, 13 May 2026 00:00:00 GMT Switch-case FSMs, function-pointer-table FSMs, hierarchical state machines. A real UART command parser that dispatches LED ON / LED OFF / BLINK 5. programming https://armhub.dev/docs/programming/c-lesson-09-structs/ https://armhub.dev/docs/programming/c-lesson-09-structs/ Wed, 13 May 2026 00:00:00 GMT Struct declaration, field access, padding and alignment, packed structs for wire formats, anonymous structs, unions as tagged sum types, bit fields, designated initializers. programming https://armhub.dev/docs/programming/libc/ https://armhub.dev/docs/programming/libc/ Wed, 13 May 2026 00:00:00 GMT The C standard library on Cortex-M and Cortex-A. newlib, newlib-nano, picolibc, glibc, musl. Syscall stubs, heap layout, re-entrancy, printf cost, and how to retarget a libc for a bare-metal target. programming https://armhub.dev/docs/cortex-m/low-power/ https://armhub.dev/docs/cortex-m/low-power/ Wed, 13 May 2026 00:00:00 GMT WFI, WFE, sleep / deep-sleep / standby. SCB.SCR.SLEEPDEEP, SLEEPONEXIT, the event registers, wake-up sources, and power consumption tradeoffs. cortex-m https://armhub.dev/docs/vendors/maxim/ https://armhub.dev/docs/vendors/maxim/ Wed, 13 May 2026 00:00:00 GMT Maxim's MAX32 Cortex-M microcontroller line under ADI. DARWIN low-power architecture, tiny WLP packages for hearables, precision analog integration, BLE radios, and the MAX78000 CNN ML accelerator. vendors https://armhub.dev/docs/vendors/maxim-max32/ https://armhub.dev/docs/vendors/maxim-max32/ Wed, 13 May 2026 00:00:00 GMT The mainstream Maxim MAX32 Cortex-M4F parts — MAX32660 in 1.6 mm WLP, MAX32670/72 with precision ADCs, MAX32650 for audio, and MAX32690 with on-die BLE 5.2. Power, peripherals, and an I2S DMA example. vendors https://armhub.dev/docs/vendors/maxim-max78000/ https://armhub.dev/docs/vendors/maxim-max78000/ Wed, 13 May 2026 00:00:00 GMT Maxim's MAX78000 and MAX78002 — Cortex-M4F microcontrollers with a dedicated convolutional neural network engine. Sub-milliwatt inference for keyword spotting, person detection, and audio classification at the edge. vendors https://armhub.dev/docs/vendors/mediatek/ https://armhub.dev/docs/vendors/mediatek/ Wed, 13 May 2026 00:00:00 GMT MediaTek is the world's second-largest fabless silicon vendor. Genio for IoT and edge AI, Filogic for Wi-Fi routers, Dimensity for smartphones, all on TSMC. vendors https://armhub.dev/docs/vendors/mediatek-filogic/ https://armhub.dev/docs/vendors/mediatek-filogic/ Wed, 13 May 2026 00:00:00 GMT MediaTek Filogic 880, 830, and 630 — quad Cortex-A53 plus Wi-Fi 7 MAC, WED packet engine, MLO, 4K-QAM. OpenWrt and vendor SDK split, real product list. vendors https://armhub.dev/docs/vendors/mediatek-genio/ https://armhub.dev/docs/vendors/mediatek-genio/ Wed, 13 May 2026 00:00:00 GMT MediaTek Genio family for IoT and edge AI. Genio 350 to Genio 1200 — Cortex-A35 to Cortex-A78, Mali GPU, NeuroPilot APU, Yocto BSP, NPU model conversion. vendors https://armhub.dev/docs/systems/medical-wearable/ https://armhub.dev/docs/systems/medical-wearable/ Wed, 13 May 2026 00:00:00 GMT Architecting a medical-grade wearable — PPG and ECG signal chain, sample rate and ADC requirements, BLE for sync, regulatory framework (IEC 60601, ISO 14971, IEC 62304), battery life via duty-cycling. systems https://armhub.dev/docs/systems/motor-foc/ https://armhub.dev/docs/systems/motor-foc/ Wed, 13 May 2026 00:00:00 GMT Field-oriented control of three-phase motors on Cortex-M. Clarke and Park transforms, d-q frame PI controllers, SVPWM, position estimation (encoder or sensorless), 10–20 kHz loop on M4F/M7 with DSP extensions or vendor FOC libraries. systems https://armhub.dev/docs/cortex-r/mpu-tcm/ https://armhub.dev/docs/cortex-r/mpu-tcm/ Wed, 13 May 2026 00:00:00 GMT Memory protection regions and tightly-coupled memories on Cortex-R — how the MPU differs from Cortex-M, the ATCM/BTCM at fixed addresses, ECC-enabled bring-up, and vector remap mechanics for fault tolerance. cortex-r https://armhub.dev/docs/cortex-m/mpu/ https://armhub.dev/docs/cortex-m/mpu/ Wed, 13 May 2026 00:00:00 GMT The Memory Protection Unit — how Cortex-M defines memory regions, what attributes they carry, how privileged and unprivileged code see different views, and the rules for stack overflow detection, RTOS task isolation, and execute-never enforcement. cortex-m https://armhub.dev/docs/cortex-a/neon-sve/ https://armhub.dev/docs/cortex-a/neon-sve/ Wed, 13 May 2026 00:00:00 GMT ARM's SIMD lineage — fixed-width NEON (Advanced SIMD), scalable-vector SVE with predicate-driven loops, and SVE2's expansion into integer, string, and crypto. Practical auto-vectorization and intrinsics for dot products and image filters. cortex-a https://armhub.dev/docs/vendors/nordic-nrf53/ https://armhub.dev/docs/vendors/nordic-nrf53/ Wed, 13 May 2026 00:00:00 GMT Nordic Semiconductor's nRF5340 — dual Cortex-M33 with TrustZone, 128 MHz application core, 64 MHz network core running BLE/Thread/Matter. Inter-processor communication, nrfx HAL, Zephyr-based nRF Connect SDK. vendors https://armhub.dev/docs/vendors/nordic-nrf91/ https://armhub.dev/docs/vendors/nordic-nrf91/ Wed, 13 May 2026 00:00:00 GMT Nordic's nRF9160 and nRF9151 — single Cortex-M33 with integrated LTE-M, NB-IoT, and GPS modem. Modem firmware, AT commands, trace-and-test split, nRF Connect SDK on Zephyr, and real-world cellular IoT design. vendors https://armhub.dev/docs/vendors/nuvoton/ https://armhub.dev/docs/vendors/nuvoton/ Wed, 13 May 2026 00:00:00 GMT Nuvoton Technology — Taiwan's quiet Cortex-M heavyweight. NuMicro M0/M23/M4/M55 portfolio, fabless-with-fab strategy, NuTool ecosystem, where it beats STM32 and where it doesn't. vendors https://armhub.dev/docs/vendors/nuvoton-m0/ https://armhub.dev/docs/vendors/nuvoton-m0/ Wed, 13 May 2026 00:00:00 GMT NuMicro Cortex-M0 entry families — NUC100, NUC200, NANO100 ultra-low-power, M031/M032 modern entry, and the LD-ROM/APROM dual-flash boot architecture that defines them. vendors https://armhub.dev/docs/vendors/nuvoton-m23/ https://armhub.dev/docs/vendors/nuvoton-m23/ Wed, 13 May 2026 00:00:00 GMT NuMicro Cortex-M23 secure family — M2351 / M2354 with TrustZone-M, ROM-based secure boot, anti-tamper, Key Store, PSA Certified Level 2 silicon. Nuvoton's answer to STM32L5. vendors https://armhub.dev/docs/vendors/nuvoton-m4/ https://armhub.dev/docs/vendors/nuvoton-m4/ Wed, 13 May 2026 00:00:00 GMT NuMicro Cortex-M4F mainstream — M451, NUC472, M480 (192 MHz with HS USB, Ethernet, CAN-FD, crypto), M487 industrial, M032 entry. Where it competes with STM32F4 and GD32F4. vendors https://armhub.dev/docs/cortex-m/nvic-priority/ https://armhub.dev/docs/cortex-m/nvic-priority/ Wed, 13 May 2026 00:00:00 GMT How the Cortex-M priority byte gets split into preempt and sub-priority groups, why PRIGROUP matters, how priority changes interact with active interrupts, and the exact rules the hardware uses to decide what runs next. cortex-m https://armhub.dev/docs/cortex-m/nvic-registers/ https://armhub.dev/docs/cortex-m/nvic-registers/ Wed, 13 May 2026 00:00:00 GMT Every NVIC register decoded — ISER, ICER, ISPR, ICPR, IABR, IPR, STIR. Address map, atomic semantics, debug behaviour, and the gotchas of write-1-to-set / write-1-to-clear. cortex-m https://armhub.dev/docs/vendors/nvidia-jetson/ https://armhub.dev/docs/vendors/nvidia-jetson/ Wed, 13 May 2026 00:00:00 GMT NVIDIA's Jetson family — Cortex-A CPUs plus NVIDIA GPU and DLA on a single SoM. From TK1 in 2014 to Thor in 2025, the JetPack SDK, TensorRT, CUDA, and why Jetson dominates serious edge AI. vendors https://armhub.dev/docs/vendors/nxp-lpc/ https://armhub.dev/docs/vendors/nxp-lpc/ Wed, 13 May 2026 00:00:00 GMT NXP's LPC microcontrollers — LPC54xxx M4+M0+ dual core, LPC55Sxx M33 with TrustZone and PUF, LPC845 low-cost M0+. State-Configurable Timer, MCUXpresso ecosystem, and how LPC differs from i.MX RT. vendors https://armhub.dev/docs/programming/ota/ https://armhub.dev/docs/programming/ota/ Wed, 13 May 2026 00:00:00 GMT Over-the-air update for embedded ARM devices. A/B banks, delta updates, secure transport, rollback safety, FOTA over BLE / Wi-Fi / cellular, and the major IoT cloud update services. programming https://armhub.dev/docs/architecture/pac-bti-mte/ https://armhub.dev/docs/architecture/pac-bti-mte/ Wed, 13 May 2026 00:00:00 GMT The three modern ARM hardware-security extensions — Pointer Authentication (PAC) against ROP, Branch Target Identification (BTI) against JOP, and Memory Tagging Extension (MTE) against use-after-free and buffer overflows. What they cost, where they're deployed, and the threat model each one defeats. architecture https://armhub.dev/docs/cortex-a/pmu/ https://armhub.dev/docs/cortex-a/pmu/ Wed, 13 May 2026 00:00:00 GMT How to profile Cortex-A workloads — PMCR control, event counters and architectural events, perf_event_open / perf record workflows, and the Statistical Profiling Extension (SPE) for sub-instruction sampling on ARMv8.2+. cortex-a https://armhub.dev/docs/architecture/pmu/ https://armhub.dev/docs/architecture/pmu/ Wed, 13 May 2026 00:00:00 GMT How ARM counts cycles, instructions, cache misses, and dozens of other events — the PMU on Cortex-A and Cortex-R, the lightweight DWT counters on Cortex-M, and how to use them to measure IPC, branch mispredict rates, and cache pressure. architecture https://armhub.dev/docs/rtos/priority-inversion/ https://armhub.dev/docs/rtos/priority-inversion/ Wed, 13 May 2026 00:00:00 GMT How a high-priority task gets blocked by a low-priority one through a shared mutex. The Mars Pathfinder story. Priority inheritance, priority ceiling protocol, and how FreeRTOS / Zephyr / ThreadX implement them. rtos https://armhub.dev/docs/peripherals/qspi-ospi/ https://armhub.dev/docs/peripherals/qspi-ospi/ Wed, 13 May 2026 00:00:00 GMT Memory-mapped access to external NOR flash over 4 or 8 parallel data lines. Single/dual/quad/octal SDR and DDR modes, the command-address-data phase model, indirect vs memory-mapped operation, and XIP from external flash on STM32 and NXP parts. peripherals https://armhub.dev/docs/vendors/rockchip/ https://armhub.dev/docs/vendors/rockchip/ Wed, 13 May 2026 00:00:00 GMT Rockchip is the largest Chinese application-processor vendor outside mobile. RK3568 for IoT gateways, RK3588 for edge AI workstations, dominant in SBC market. vendors https://armhub.dev/docs/vendors/rockchip-rk3568/ https://armhub.dev/docs/vendors/rockchip-rk3568/ Wed, 13 May 2026 00:00:00 GMT Rockchip RK3566 and RK3568. Quad Cortex-A55, Mali-G52, NPU, dual GbE, PCIe Gen3. Buildroot and Armbian, mainline kernel status, device-tree examples. vendors https://armhub.dev/docs/vendors/rockchip-rk3588/ https://armhub.dev/docs/vendors/rockchip-rk3588/ Wed, 13 May 2026 00:00:00 GMT Rockchip RK3588 and RK3588S. Quad Cortex-A76 plus quad Cortex-A55, Mali-G610, 6 TOPS NPU, 8K decode. RKNN Toolkit, Orange Pi 5 Plus, Rock 5B, edge AI use cases. vendors https://armhub.dev/docs/rtos/rt-thread/ https://armhub.dev/docs/rtos/rt-thread/ Wed, 13 May 2026 00:00:00 GMT RT-Thread RTOS — Chinese-developed, dominant in Asia, object-oriented kernel with a package manager, finsh shell, lwIP/FAT integration, SMP support, and optional MMU. Architecture, components, and how it differs from FreeRTOS. rtos https://armhub.dev/docs/rtos/scheduling/ https://armhub.dev/docs/rtos/scheduling/ Wed, 13 May 2026 00:00:00 GMT Real-time scheduling theory and practice. Priority-based preemptive vs cooperative, rate-monotonic analysis, the Liu-Layland bound, deadline-monotonic, EDF, time-slicing, and how to assign priorities to a real workload. rtos https://armhub.dev/docs/rtos/tutorial/ https://armhub.dev/docs/rtos/tutorial/ Wed, 13 May 2026 00:00:00 GMT A hands-on 10-lesson tutorial. Why an RTOS, your first task, blocking primitives, queues, event groups, mutexes done right, tickless idle, debugging — all on real silicon. rtos https://armhub.dev/docs/cortex-r/safety-standards/ https://armhub.dev/docs/cortex-r/safety-standards/ Wed, 13 May 2026 00:00:00 GMT How Cortex-R-based designs meet functional safety standards — ISO 26262 ASIL classification, IEC 61508 SIL, DO-178C for avionics, IEC 62304 for medical. What ARM ships as "safety packs" and what the integrator still owns. cortex-r https://armhub.dev/docs/rtos/safety-rtos/ https://armhub.dev/docs/rtos/safety-rtos/ Wed, 13 May 2026 00:00:00 GMT Safety-certified real-time operating systems. SAFERTOS, Azure RTOS ThreadX certifications, PikeOS, QNX, INTEGRITY, VxWorks Cert. IEC 61508, ISO 26262, DO-178C, IEC 62304, and the artifacts required. rtos https://armhub.dev/docs/peripherals/sdmmc/ https://armhub.dev/docs/peripherals/sdmmc/ Wed, 13 May 2026 00:00:00 GMT The SD/MMC card peripheral on Cortex-M — protocol layers from CMD0/CMD1 initialization through UHS-I speeds, 4-bit data line operation, the SDIO variant for Wi-Fi and other non-card devices, and FATFS integration. peripherals https://armhub.dev/docs/peripherals/smbus/ https://armhub.dev/docs/peripherals/smbus/ Wed, 13 May 2026 00:00:00 GMT System Management Bus and Power Management Bus — extensions on top of I²C with packet error checking, address resolution, alert response, and the standardized PMBus power-supply command set used by every modern point-of-load converter. peripherals https://armhub.dev/docs/cortex-a/smp/ https://armhub.dev/docs/cortex-a/smp/ Wed, 13 May 2026 00:00:00 GMT Symmetric multiprocessing on Cortex-A clusters — CCI/CCN interconnect, MESI/MOESI cache coherency, LDXR/STXR spinlocks, inter-processor interrupts via SGIs, secondary CPU boot via PSCI, and the Linux scheduler's view. cortex-a https://armhub.dev/docs/tools/static-analysis/ https://armhub.dev/docs/tools/static-analysis/ Wed, 13 May 2026 00:00:00 GMT Catching bugs before the firmware runs — clang-tidy, scan-build, Coverity, Polyspace, PC-lint Plus, Cppcheck, MISRA-C 2012 conformance, and how to make CI gating actually useful. tools https://armhub.dev/docs/vendors/stm32-lowpower/ https://armhub.dev/docs/vendors/stm32-lowpower/ Wed, 13 May 2026 00:00:00 GMT STM32 L series (M3/M4/M33 low-power) and U series (M33 with TrustZone, ultra-low-power), stop-mode currents below 1 µA, LPTIM and LPUART autonomous peripherals, designing a battery-powered system from the silicon up. vendors https://armhub.dev/docs/vendors/stm32-mainstream/ https://armhub.dev/docs/vendors/stm32-mainstream/ Wed, 13 May 2026 00:00:00 GMT The mainstream STM32 lines — F-series general-purpose M3/M4/M7, G-series cost-optimised M4 with ART accelerator, H-series M7 with cache and Chrom-ART. Architecture differences, ecosystem, and how to pick. vendors https://armhub.dev/docs/vendors/stm32-wireless/ https://armhub.dev/docs/vendors/stm32-wireless/ Wed, 13 May 2026 00:00:00 GMT STM32WB dual-core BLE/Thread/Zigbee with a dedicated Cortex-M0+ radio core, STM32WL sub-GHz LoRa with M4 application and M0+ Sub-GHz radio. How the application/network split works, IPC, and coexistence. vendors https://armhub.dev/docs/tools/swo/ https://armhub.dev/docs/tools/swo/ Wed, 13 May 2026 00:00:00 GMT Serial Wire Output and the Instrumentation Trace Macrocell — non-halting printf, exception tracing, PC sampling and DWT counters streamed over a single pin at multi-megabit rates. tools https://armhub.dev/docs/cortex-m/scb/ https://armhub.dev/docs/cortex-m/scb/ Wed, 13 May 2026 00:00:00 GMT ICSR, AIRCR, SCR, CCR, SHPR1-3, SHCSR, CFSR, HFSR, MMFAR, BFAR — every SCB register decoded. Reset, sleep, fault handling, exception priority, and unaligned-access trapping. cortex-m https://armhub.dev/docs/cortex-m/tail-chain/ https://armhub.dev/docs/cortex-m/tail-chain/ Wed, 13 May 2026 00:00:00 GMT The two NVIC optimizations that hide exception-entry latency. Cycle-by-cycle: standard entry, tail-chain savings, late-arrival upgrade path. cortex-m https://armhub.dev/docs/vendors/ti-sitara/ https://armhub.dev/docs/vendors/ti-sitara/ Wed, 13 May 2026 00:00:00 GMT Texas Instruments Sitara processor family — Cortex-A53 / Cortex-R5F / Cortex-M4F heterogeneous SoCs. AM62x for HMI and edge AI, AM64x for industrial fieldbus, AM243x as full-R5 safety controller. PRU, Linux + RTOS split. vendors https://armhub.dev/docs/rtos/tickless/ https://armhub.dev/docs/rtos/tickless/ Wed, 13 May 2026 00:00:00 GMT Power-aware RTOS idle. Conventional 1ms tick costs a wakeup every millisecond. Tickless skips ticks when no task is ready, sleeps until the next real deadline. FreeRTOS portSUPPRESS_TICKS_AND_SLEEP, Zephyr CONFIG_TICKLESS_KERNEL, wakeup sources, and catch-up logic. rtos https://armhub.dev/docs/cortex-a/tlb/ https://armhub.dev/docs/cortex-a/tlb/ Wed, 13 May 2026 00:00:00 GMT How Cortex-A cores translate virtual to physical addresses — split L1 TLBs, unified L2 TLB, ASIDs and VMIDs, page-walk caches, the TTL hint, and the real cost of a TLB miss in a modern OoO core. cortex-a https://armhub.dev/docs/architecture/trustzone-m/ https://armhub.dev/docs/architecture/trustzone-m/ Wed, 13 May 2026 00:00:00 GMT How TrustZone for ARMv8-M partitions a Cortex-M chip into Secure and Non-secure worlds — SAU, IDAU, NSC regions, the SG gateway instruction, TT probes, SecureFault, and how TF-M ties it together. architecture https://armhub.dev/docs/peripherals/uart-lin-iso7816/ https://armhub.dev/docs/peripherals/uart-lin-iso7816/ Wed, 13 May 2026 00:00:00 GMT Two specialist protocols layered on top of the same USART hardware — LIN for low-cost automotive networking and ISO 7816 for contact smartcards. Frame structure, hardware support on STM32, and the timing rules that matter in production. peripherals https://armhub.dev/docs/peripherals/usb-host/ https://armhub.dev/docs/peripherals/usb-host/ Wed, 13 May 2026 00:00:00 GMT Acting as a USB host on Cortex-M — enumeration, transfer scheduling, the controller stack from PHY up to class drivers, and the dual-role OTG mechanism that lets a single port flip between host and device based on the ID pin. peripherals https://armhub.dev/docs/cortex-m/vector-table/ https://armhub.dev/docs/cortex-m/vector-table/ Wed, 13 May 2026 00:00:00 GMT Vector table layout, VTOR register, relocating to RAM for bootloader splits and dynamic dispatch, alignment requirements, and the bring-up gotchas. cortex-m https://armhub.dev/docs/cortex-a/virtualization/ https://armhub.dev/docs/cortex-a/virtualization/ Wed, 13 May 2026 00:00:00 GMT How Cortex-A virtualization works at EL2 — stage-1 and stage-2 translation, VHE for type-2 hypervisors, vGIC for interrupt delivery, the HVC/SVC/SMC instruction split, and what KVM, Xen, and Jailhouse do with all of it. cortex-a https://armhub.dev/docs/programming/volatile-mmio/ https://armhub.dev/docs/programming/volatile-mmio/ Wed, 13 May 2026 00:00:00 GMT What volatile actually guarantees, why MMIO without it is broken, read-modify-write hazards on peripheral registers, bit-banding on M3/M4, and the Cortex-M memory-ordering rules for device vs normal memory. programming https://armhub.dev/docs/peripherals/adc/ https://armhub.dev/docs/peripherals/adc/ Tue, 12 May 2026 00:00:00 GMT Analog-to-digital and digital-to-analog converters — sampling, resolution, references, oversampling, and the signal-chain tradeoffs you make without realising it. peripherals https://armhub.dev/docs/architecture/armv7m-armv8m/ https://armhub.dev/docs/architecture/armv7m-armv8m/ Tue, 12 May 2026 00:00:00 GMT What changed between ARMv7-M and ARMv8-M — TrustZone, stack limits, security states — and what stayed the same. architecture https://armhub.dev/docs/systems/automotive-ecu/ https://armhub.dev/docs/systems/automotive-ecu/ Tue, 12 May 2026 00:00:00 GMT Inside a typical body-control or chassis ECU — Cortex-R52 lockstep + Cortex-M I/O cores, CAN-FD, ISO 26262, AUTOSAR Classic. The firmware that keeps the airbag from misfiring. systems https://armhub.dev/docs/cortex-a/boot-and-exception-levels/ https://armhub.dev/docs/cortex-a/boot-and-exception-levels/ Tue, 12 May 2026 00:00:00 GMT From silicon reset to Linux init — the multi-stage boot chain on ARMv8-A, and what runs in each Exception Level. cortex-a https://armhub.dev/docs/tools/build/ https://armhub.dev/docs/tools/build/ Tue, 12 May 2026 00:00:00 GMT CMake, Make, Meson, west, scons — what to use for a new Cortex-M project, and how to glue the toolchain together. tools https://armhub.dev/docs/programming/cpp/ https://armhub.dev/docs/programming/cpp/ Tue, 12 May 2026 00:00:00 GMT Modern C++ in firmware — constexpr, std::array, templates, and the language features to embrace or avoid on embedded. programming https://armhub.dev/docs/cortex-a/caches/ https://armhub.dev/docs/cortex-a/caches/ Tue, 12 May 2026 00:00:00 GMT Multi-level caches on ARM apps cores — L1/L2/L3 hierarchy, the cache coherency protocol, and where DMA still surprises you. cortex-a https://armhub.dev/docs/peripherals/can/ https://armhub.dev/docs/peripherals/can/ Tue, 12 May 2026 00:00:00 GMT Controller Area Network — bit timing, arbitration, message filtering, CAN-FD, and why the network length actually matters. peripherals https://armhub.dev/docs/programming/cmsis/ https://armhub.dev/docs/programming/cmsis/ Tue, 12 May 2026 00:00:00 GMT The Cortex Microcontroller Software Interface Standard — what's in it, why every vendor ships it, and the parts you actually use. programming https://armhub.dev/docs/cortex-a/overview/ https://armhub.dev/docs/cortex-a/overview/ Tue, 12 May 2026 00:00:00 GMT ARM's applications-class cores — what makes them different from Cortex-M, and what a firmware engineer needs to know when stepping up to A-profile. cortex-a https://armhub.dev/docs/cortex-m/m3/ https://armhub.dev/docs/cortex-m/m3/ Tue, 12 May 2026 00:00:00 GMT The original mainstream Cortex-M. Full Thumb-2, hardware divide, bit-banding — still everywhere despite being twenty years old. cortex-m https://armhub.dev/docs/cortex-m/m4/ https://armhub.dev/docs/cortex-m/m4/ Tue, 12 May 2026 00:00:00 GMT The workhorse of the Cortex-M family — ARMv7E-M, 3-stage pipeline, DSP extensions, optional FPU. Everything you need to ship firmware on M4. cortex-m https://armhub.dev/docs/cortex-m/m7/ https://armhub.dev/docs/cortex-m/m7/ Tue, 12 May 2026 00:00:00 GMT The first superscalar Cortex-M. Caches, TCMs, double-precision FPU, six-stage dual-issue pipeline. Real performance, real complexity. cortex-m https://armhub.dev/docs/cortex-r/overview/ https://armhub.dev/docs/cortex-r/overview/ Tue, 12 May 2026 00:00:00 GMT ARM's real-time application-class cores — built for hard real-time, often in lockstep, with MPUs instead of MMUs and tightly coupled memories. cortex-r https://armhub.dev/docs/peripherals/dma/ https://armhub.dev/docs/peripherals/dma/ Tue, 12 May 2026 00:00:00 GMT Direct Memory Access — moving bytes without the CPU, channel/stream architectures, request signals, double-buffering, and cache coherency on Cortex-M7. peripherals https://armhub.dev/docs/systems/drone-flight-controller/ https://armhub.dev/docs/systems/drone-flight-controller/ Tue, 12 May 2026 00:00:00 GMT Inside a Pixhawk-class flight controller — Cortex-M7 at 480 MHz, 8 kHz attitude loop, IMU + barometer + GPS, DSHOT ESCs, PX4 on NuttX. systems https://armhub.dev/docs/programming/embedded-c/ https://armhub.dev/docs/programming/embedded-c/ Tue, 12 May 2026 00:00:00 GMT The C patterns that show up in every Cortex-M codebase — volatile, register access, alignment, packed structs, weak symbols, and what they actually mean. programming https://armhub.dev/docs/systems/ev-charger/ https://armhub.dev/docs/systems/ev-charger/ Tue, 12 May 2026 00:00:00 GMT Inside a 7.2–11.5 kW home EV charger — Cortex-M7 control, Wi-Fi MCU, the J1772 control-pilot dance, residual-current protection, and OCPP cloud comms. systems https://armhub.dev/docs/rtos/freertos/ https://armhub.dev/docs/rtos/freertos/ Tue, 12 May 2026 00:00:00 GMT The pragmatic RTOS — task creation, scheduling, the Cortex-M port internals, queues, semaphores, software timers, and tickless idle. rtos https://armhub.dev/docs/tools/gdb/ https://armhub.dev/docs/tools/gdb/ Tue, 12 May 2026 00:00:00 GMT Using GDB with Cortex-M — connecting to a probe, set/load, breakpoints, watchpoints, peripheral views, and the .gdbinit that saves you 50% of bring-up time. tools https://armhub.dev/docs/peripherals/gpio/ https://armhub.dev/docs/peripherals/gpio/ Tue, 12 May 2026 00:00:00 GMT The most fundamental peripheral — push-pull, open-drain, pull-up, pull-down, alternate functions, atomic set-reset, EXTI. Patterns that work on every Cortex-M. peripherals https://armhub.dev/docs/peripherals/i2c/ https://armhub.dev/docs/peripherals/i2c/ Tue, 12 May 2026 00:00:00 GMT The two-wire bus — addressing, clock stretching, multi-master, 7-bit and 10-bit addresses, and why your I²C peripheral hung again. peripherals https://armhub.dev/docs/systems/motor-drive/ https://armhub.dev/docs/systems/motor-drive/ Tue, 12 May 2026 00:00:00 GMT Inside a 1–50 kW industrial servo drive — Cortex-M4F or M7, FOC at 20 kHz, current-sense ADC synced to inverter PWM, encoder feedback, CANopen/EtherCAT. systems https://armhub.dev/docs/vendors/infineon/ https://armhub.dev/docs/vendors/infineon/ Tue, 12 May 2026 00:00:00 GMT Infineon's Cortex-M lines — XMC (industrial), PSoC (programmable analog + digital), and the TriCore-based AURIX for automotive. vendors https://armhub.dev/docs/programming/inline-asm/ https://armhub.dev/docs/programming/inline-asm/ Tue, 12 May 2026 00:00:00 GMT When and how to use inline assembly on Cortex-M — GCC syntax, clobbers, the LLVM extended-asm rules, and what assembly actually buys you. programming https://armhub.dev/docs/programming/linker-scripts/ https://armhub.dev/docs/programming/linker-scripts/ Tue, 12 May 2026 00:00:00 GMT GNU ld linker scripts for Cortex-M — memory regions, section placement, AT-load addresses, alignment, and the directives you actually need. programming https://armhub.dev/docs/cortex-r/lockstep/ https://armhub.dev/docs/cortex-r/lockstep/ Tue, 12 May 2026 00:00:00 GMT How dual-core lockstep delivers ASIL-D readiness on Cortex-R — and where the software still has to do work. cortex-r https://armhub.dev/docs/architecture/memory-model/ https://armhub.dev/docs/architecture/memory-model/ Tue, 12 May 2026 00:00:00 GMT How loads and stores are ordered on ARM — relaxed by default, with explicit barriers (DMB, DSB, ISB) where you need them. Plus the Cortex-M memory map. architecture https://armhub.dev/docs/vendors/microchip/ https://armhub.dev/docs/vendors/microchip/ Tue, 12 May 2026 00:00:00 GMT Microchip's Cortex-M lines — the inherited Atmel SAM family and Microchip's own PIC32C Cortex-M parts. vendors https://armhub.dev/docs/cortex-a/mmu/ https://armhub.dev/docs/cortex-a/mmu/ Tue, 12 May 2026 00:00:00 GMT How ARMv8-A translates virtual addresses to physical — page table levels, TLBs, memory attributes, and the AArch64 translation regime. cortex-a https://armhub.dev/docs/vendors/nordic/ https://armhub.dev/docs/vendors/nordic/ Tue, 12 May 2026 00:00:00 GMT The Bluetooth-first Cortex-M family — softdevice architecture, EasyDMA, the nRF Connect SDK / Zephyr migration. vendors https://armhub.dev/docs/cortex-m/nvic/ https://armhub.dev/docs/cortex-m/nvic/ Tue, 12 May 2026 00:00:00 GMT The Nested Vectored Interrupt Controller — how priorities, preemption, pending, and active states actually interact. With registers and timing analysis. cortex-m https://armhub.dev/docs/vendors/nxp/ https://armhub.dev/docs/vendors/nxp/ Tue, 12 May 2026 00:00:00 GMT NXP's Cortex-M lines — Kinetis for industrial, LPC for embedded mainstream, i.MX RT for crossover MCUs running at GHz speeds. vendors https://armhub.dev/docs/tools/openocd/ https://armhub.dev/docs/tools/openocd/ Tue, 12 May 2026 00:00:00 GMT ST-Link, J-Link, CMSIS-DAP, Black Magic — the debug probes you'll meet, what OpenOCD does, and the alternatives (pyOCD, probe-rs). tools https://armhub.dev/docs/tools/sim/ https://armhub.dev/docs/tools/sim/ Tue, 12 May 2026 00:00:00 GMT Simulating Cortex-M without hardware — when emulation actually works, and when you should just buy the dev board. tools https://armhub.dev/docs/vendors/raspberry/ https://armhub.dev/docs/vendors/raspberry/ Tue, 12 May 2026 00:00:00 GMT The hobbyist-friendly Cortex-M from Raspberry Pi — dual-core, PIO, excellent docs, and now the dual-Arm/RISC-V RP2350. vendors https://armhub.dev/docs/vendors/renesas/ https://armhub.dev/docs/vendors/renesas/ Tue, 12 May 2026 00:00:00 GMT Renesas's ARM portfolio — the RA family (modern Cortex-M from the Synergy line) and RZ (Cortex-A/R) for industrial. vendors https://armhub.dev/docs/programming/rust/ https://armhub.dev/docs/programming/rust/ Tue, 12 May 2026 00:00:00 GMT The modern path — cortex-m, embedded-hal, RTIC, Embassy. What Rust gives you that C doesn't, and where the rough edges still are. programming https://armhub.dev/docs/vendors/silabs/ https://armhub.dev/docs/vendors/silabs/ Tue, 12 May 2026 00:00:00 GMT Silicon Labs's energy-friendly Cortex-M parts — and their EFR32 wireless line that owns much of the Zigbee / Thread / Matter market. vendors https://armhub.dev/docs/systems/smart-thermostat/ https://armhub.dev/docs/systems/smart-thermostat/ Tue, 12 May 2026 00:00:00 GMT Inside a Nest / ecobee class thermostat — Cortex-M33 + Wi-Fi/Thread radio, capacitive touch, e-paper or LCD, HVAC relays, Matter, and how to run on 24 VAC stolen-power. systems https://armhub.dev/docs/systems/smartwatch/ https://armhub.dev/docs/systems/smartwatch/ Tue, 12 May 2026 00:00:00 GMT How a wearable runs 5–15 days on a 200 mAh battery — Cortex-M33 + BLE radio, sensor fusion, AMOLED, GATT services, and where Wear OS departs from this entirely. systems https://armhub.dev/docs/peripherals/spi/ https://armhub.dev/docs/peripherals/spi/ Tue, 12 May 2026 00:00:00 GMT Synchronous serial — clock polarity and phase, master/slave, multi-slave, full-duplex DMA, and the gotchas you only learn on the bench. peripherals https://armhub.dev/docs/programming/startup/ https://armhub.dev/docs/programming/startup/ Tue, 12 May 2026 00:00:00 GMT Writing the code that runs before main — vector table layout, Reset_Handler, .data/.bss init, C++ static constructors, and what newlib needs. programming https://armhub.dev/docs/vendors/stm32/ https://armhub.dev/docs/vendors/stm32/ Tue, 12 May 2026 00:00:00 GMT The most prolific Cortex-M family — F0 through U5, plus the H7 / H5 high-end. Strengths, ecosystem, and the right line for the job. vendors https://armhub.dev/docs/systems/overview/ https://armhub.dev/docs/systems/overview/ Tue, 12 May 2026 00:00:00 GMT How real products are actually built — block-level walkthroughs of seven everyday embedded systems, from Wi-Fi routers to flight controllers. systems https://armhub.dev/docs/cortex-m/systick/ https://armhub.dev/docs/cortex-m/systick/ Tue, 12 May 2026 00:00:00 GMT The universal Cortex-M 24-bit downcounter — how it works, how to use it for an RTOS tick or a delay, and what its limits are. cortex-m https://armhub.dev/docs/vendors/ti/ https://armhub.dev/docs/vendors/ti/ Tue, 12 May 2026 00:00:00 GMT TI's ARM portfolio — Tiva (was Stellaris, M4), MSP432 (low-power M4F), Hercules (Cortex-R safety). vendors https://armhub.dev/docs/architecture/isa-family/ https://armhub.dev/docs/architecture/isa-family/ Tue, 12 May 2026 00:00:00 GMT A field guide to ARM's instruction set architectures — from ARMv6-M on tiny microcontrollers to ARMv9-A on flagship phones — and how the modern Cortex lineup maps onto them. architecture https://armhub.dev/docs/cortex-m/lineup/ https://armhub.dev/docs/cortex-m/lineup/ Tue, 12 May 2026 00:00:00 GMT Every Cortex-M core from M0 to M85 — what changed, what it costs, when to pick it. cortex-m https://armhub.dev/docs/architecture/exception-model/ https://armhub.dev/docs/architecture/exception-model/ Tue, 12 May 2026 00:00:00 GMT How Cortex-M handles interrupts, faults, and supervisor calls — vector tables, exception priorities, stack frames, and tail-chaining. architecture https://armhub.dev/docs/rtos/landscape/ https://armhub.dev/docs/rtos/landscape/ Tue, 12 May 2026 00:00:00 GMT FreeRTOS, Zephyr, ThreadX, RT-Thread, Mbed OS, RIOT — what they are, where they win, and how to choose for a new project. rtos https://armhub.dev/docs/rtos/threadx/ https://armhub.dev/docs/rtos/threadx/ Tue, 12 May 2026 00:00:00 GMT The certifiable RTOS — fast context switches, deterministic primitives, and pre-existing safety certifications for IEC 61508 and ISO 26262. rtos https://armhub.dev/docs/peripherals/timers/ https://armhub.dev/docs/peripherals/timers/ Tue, 12 May 2026 00:00:00 GMT General-purpose timers, advanced timers, input capture, output compare, PWM, encoder mode — the most flexible peripheral on the chip. peripherals https://armhub.dev/docs/tools/toolchains/ https://armhub.dev/docs/tools/toolchains/ Tue, 12 May 2026 00:00:00 GMT arm-none-eabi-gcc, LLVM/clang, IAR, Keil/ARM Compiler — the realistic options for compiling Cortex-M code, with the flags that actually matter. tools https://armhub.dev/docs/architecture/trustzone/ https://armhub.dev/docs/architecture/trustzone/ Tue, 12 May 2026 00:00:00 GMT How TrustZone partitions ARM systems into secure and non-secure worlds — on Cortex-M (per-access SAU/IDAU) and on Cortex-A (per-CPU NS bit). architecture https://armhub.dev/docs/peripherals/uart/ https://armhub.dev/docs/peripherals/uart/ Tue, 12 May 2026 00:00:00 GMT Asynchronous serial — bit rates, framing, parity, hardware flow control, DMA, and the subtle differences across vendor implementations. peripherals https://armhub.dev/docs/peripherals/usb/ https://armhub.dev/docs/peripherals/usb/ Tue, 12 May 2026 00:00:00 GMT USB Full-Speed device class on Cortex-M — descriptors, endpoints, control transfers, CDC ACM, and the gotchas of bring-up. peripherals https://armhub.dev/docs/systems/wifi-router/ https://armhub.dev/docs/systems/wifi-router/ Tue, 12 May 2026 00:00:00 GMT How a $150 Wi-Fi 6 router is actually built — quad Cortex-A53, dedicated MAC/PHY, NPU offload, OpenWrt. Plus where ASUS, Linksys, GL.iNet differ. systems https://armhub.dev/docs/rtos/zephyr/ https://armhub.dev/docs/rtos/zephyr/ Tue, 12 May 2026 00:00:00 GMT The Linux-Foundation RTOS — device tree, Kconfig, west, drivers, networking. The whole-OS approach to embedded. rtos