BERGSONNE

API summary

The SDK’s public core_ API in one place, with the curated hal_ / ll_ surface beneath it — grouped by subsystem in the same order as the guides and the implementation status. Switch the Core / HAL / LL toggle at the top of the sidebar to view a layer. It’s generated from the same manifests the guides use, so it stays in sync with the headers automatically. Left out on purpose: internal helpers, macros (such as core_tiles_pal(), covered in the tile PAL guide), and the register-level plumbing inside the HAL and LL headers.

261 Core functions · across 16 subsystems

Systemguide →

FunctionAccessDescription
core_delay_ms(uint32_t ms)Tier 2Blocking delay in milliseconds.
core_delay_us(uint32_t us)Tier 2Blocking delay in microseconds. For delays > 1 ms prefer `delay_ms` — it won't starve the rest of the system as long.
core_millis(void)Tier 2Milliseconds since boot (wraps at ~49 days).
core_timeout(uint32_t start, uint32_t ms)Tier 2Check if a timeout has elapsed. start: value returned by core_millis() at the beginning ms: timeout duration in milliseconds Returns 1 if expired, 0 otherwise.
core_cycle_init(void)Tier 1Enable the DWT cycle counter. Idempotent; call once at startup.
core_delay_cycles(uint32_t cycles)Tier 1Busy-wait `cycles` CPU cycles (≈ ±a few cycles of loop overhead).
core_delay_ns(uint32_t ns)Tier 1Busy-wait `ns` nanoseconds (rounds to whole CPU cycles).
core_watchdog_start(uint32_t timeout_ms)Tier 2Start the independent watchdog with a timeout in milliseconds. Selects the best prescaler/reload combination automatically. Common values: 1000, 2000, 5000, 10000 (max ~28000). WARNING: Once started, the IWDG cannot be stopped, and it keeps running in Stop and Standby. core_stop_for() wakes to feed it; core_standby_for() refuses sleeps longer than half the timeout.
core_watchdog_feed(void)Tier 2Feed the watchdog. Must be called before the timeout expires. On ROM-DFU builds this also retires the brick-recovery strike counter, once, after the app has run for max(10 s, 2 x the timeout) — no call needed.
core_watchdog_running(void)Tier 1Returns 1 if this firmware has started the watchdog (core_watchdog_start).
core_watchdog_sleep_chunk_ms(void)Tier 1The longest a sleep may run between feeds while the watchdog runs: half its timeout, in ms. 0 when the watchdog isn't running. The RTC that times the sleep and the IWDG share the LSI, so the margin holds even when the LSI is far from nominal (the L0's is 26-56 kHz).
core_watchdog_caused_reset(void)Tier 1Check if the last reset was caused by the watchdog. On ROM_DFU builds, core_init() reads and clears the hardware flag early (for the strike counter), stashing the cause in reserved SRAM — so prefer that when it's valid; otherwise fall back to the raw RCC_CSR flag.
core_watchdog_clear_flags(void)Tier 1Clear all reset flags (call after checking cause).
core_watchdog_debug_freeze(void)Tier 1Freeze the IWDG while the core is halted under a debugger, so a breakpoint doesn't let the watchdog reset the chip out from under an SWD session. Firmware-side so it holds for any probe/toolchain (rev b exposes SWD on L4).
core_fault_set_callback(hal_fault_callback_t cb)Tier 1Register a fault callback, run in fault context before the SOS blink (and before the L4's USB register dump). Keep it minimal: no heap, no interrupts.
core_recovery_note_boot(void)Tier 1Account for this boot and return the running strike count. Call once, very early in core_init(), before clocks/user code.
core_recovery_over_limit(uint32_t strikes)Tier 1True once we've had enough consecutive watchdog resets to give up on the app.
core_recovery_clear(void)Tier 1Clear the strike counter now. core_watchdog_feed() already does this once the app has run healthy for max(10 s, 2x the timeout); call this only to declare health earlier than that.
core_debug_init(void)Tier 1Initialize SWO debug output using the project's SYSCLK_HZ (no-op on Core.ST.L0).
core_debug_print(const char * str)Tier 1Print a string via SWO (no formatting).

Onboard LEDguide →

FunctionAccessDescription
core_led_on(void)Tier 2Turn the onboard LED on. Simplest possible light control — useful alongside blink/heartbeat when the user wants explicit on/off state rather than a timed pattern.
core_led_off(void)Tier 2Turn the onboard LED off.
core_led_toggle(void)Tier 2Flip the onboard LED's current state. Non-blocking — no delay. Good for driving the LED from an event handler that fires at a rate you've already chosen (e.g., a pad-edge ISR on a button).
core_led_blink(int n, int on_ms, int off_ms)Tier 2Blink the LED n times. Each cycle turns the LED on for on_ms milliseconds and off for off_ms milliseconds. Blocking — returns after the last off period. A short on_ms (under 50 ms) is the on-time at 3.3 V: at lower supply voltages it is lengthened so the blink looks as bright (the off-time shrinks to keep the rhythm). See core_led_heartbeat().
core_led_heartbeat(int period_ms, int on_ms)Tier 2Start a free-running, asymmetric heartbeat on the onboard LED. Set it up once (e.g. at startup) and it runs on its own — the LED turns on for on_ms, off for the rest of period_ms, repeating forever. Serviced from the 1 ms SysTick interrupt, so it does NOT block your main loop the way a toggle-and-delay would: the loop stays free for tile reads and logic. Call again at any time to change the rhythm; pass period_ms = 0 to stop the heartbeat (the LED is left off). on_ms is clamped to period_ms. Brightness holds across the supply: a short on_ms (under 50 ms, e.g. a 2 ms blip) is the on-time at 3.3 V, and is lengthened as VDD drops (about 32 ms at 1.8 V), because the LED carries far less current there and the eye adds up the light of a short flash. VDD is read through VREFINT when the heartbeat is set (at most once a minute) on the L0, L4 and W5; the H5 uses the on-time as given. Examples: heartbeat(1000, 2) — a 1 Hz 2 ms blip, the same brightness at any VDD. heartbeat(1000, 100) — a 1 Hz "blip": 100 ms on, 900 ms off. heartbeat(500, 250) — a steady 1 Hz, 50%-duty pulse. Defined in core_led.c (not header-only) because it owns persistent state shared with the SysTick handler.
core_led_init(void)Tier 1Enable the GPIO clock and configure the LED pin as a push-pull output. Call once after core_init(). The LED starts in the off state.
core_led_sos(void)Tier 1Blink the SOS pattern (3 short, 3 long, 3 short) in an infinite loop. Use for unrecoverable errors. This function never returns.

GPIOguide →

FunctionAccessDescription
core_pad_write(uint8_t pad, int state)Tier 2Set a pad high (ON) or low (OFF).
core_pad_read(uint8_t pad)Tier 2Read a pad. Returns 0 or 1.
core_pad_toggle(uint8_t pad)Tier 2Toggle a pad output.
core_pad_output(uint8_t pad)Tier 1Configure a pad as push-pull output (default).
core_pad_output_od(uint8_t pad, uint32_t pull)Tier 1Configure a pad as open-drain output with optional pull resistor. Use PULL_UP for a wired-AND / I2C-style bus, PULL_NONE for external pull.
core_pad_input(uint8_t pad, uint32_t pull)Tier 1Configure a pad as input with pull resistor.
core_pad_resolve(uint8_t pad)Tier 1Resolve a pad to a fast handle once, outside the hot loop.
core_pad_fast_set(core_pad_fast_t h)Tier 1Drive the resolved pad high — single BSRR write.
core_pad_fast_clear(core_pad_fast_t h)Tier 1Drive the resolved pad low — single BSRR write.
core_pad_fast_write(core_pad_fast_t h, int state)Tier 1Drive the resolved pad to `state` (0/1) — single BSRR write.
core_pad_fast_read(core_pad_fast_t h)Tier 1Read the resolved pad — single IDR load. Returns 0 or 1.
core_pad_bulk_write(GPIO_TypeDef * port, uint32_t set_mask, uint32_t clear_mask)Tier 1Bulk update many pins on ONE port in a single atomic BSRR write: pins in `set_mask` go high, pins in `clear_mask` go low (set wins on overlap, per BSRR). Build the masks from the generated PAD_n_MASK defines. Useful for synchronized buses / LED matrices without per-pad jitter.
core_pad_analog(uint8_t pad)Tier 1Configure a pad as analog (for ADC, DAC, comparator).
core_pad_speed(uint8_t pad, uint32_t speed)Tier 1Set the output speed (slew rate) of a pad. Use SPEED_LOW / SPEED_MED / SPEED_HIGH / SPEED_VHIGH. Only affects outputs — input pads ignore this setting.
core_pad_on_change(uint8_t pad, uint32_t edge, hal_callback_t cb, void * ctx)Tier 1Register an edge-triggered callback on a pad. The pad is automatically configured as input with a sensible pull resistor based on edge direction: rising → pull-down (idle low) falling → pull-up (idle high) both → no pull (external bias expected)
core_pad_on_change_stop(uint8_t pad)Tier 1Stop the interrupt on a pad.

UARTguide →

FunctionAccessDescription
core_serial_print_bus(uint8_t bus, const char * str)Tier 2Write a null-terminated string to `bus` (blocking). Returns 0 on success or -1 on undeclared bus. The most-common DSL pattern — "drop a debug line on UART2" — is one line: serial.print(2, "ready\\n");
core_serial_putc_bus(uint8_t bus, uint8_t byte)Tier 2Write a single byte to `bus` (blocking). Returns 0 on success or -1 on undeclared bus.
core_serial_init(hal_uart_t * h, USART_TypeDef * instance, const hal_uart_config_t * cfg)Tier 1Initialize a UART instance. Clock is auto-resolved from PCLK1_HZ (core_config.h).
core_serial_init_clk(hal_uart_t * h, USART_TypeDef * instance, uint32_t pclk_hz, const hal_uart_config_t * cfg)Tier 1
core_serial_write(hal_uart_t * h, const uint8_t * data, uint32_t len)Tier 1Transmit a buffer (blocking).
core_serial_print(hal_uart_t * h, const char * str)Tier 1Transmit a null-terminated string (blocking).
core_serial_putc(hal_uart_t * h, uint8_t byte)Tier 1Transmit a single byte (blocking).
core_serial_available(hal_uart_t * h)Tier 1Number of bytes available in the RX buffer.
core_serial_getc(hal_uart_t * h)Tier 1Receive a single byte (blocking -- waits for data).
core_serial_read(hal_uart_t * h, uint8_t * buf, uint16_t max_len)Tier 1Read available bytes from the RX ring buffer (non-blocking). Returns number of bytes read.
core_serial_handle_for_bus(uint8_t bus)Tier 1The UART handle for a bus id declared in config.json, or NULL if the project doesn't declare that bus. Emitted per project by coregen into core_init.c (when the project declares any USART); the *_bus helpers below resolve their handle through it. Forward-declared here rather than `#include "core_init.h"` so this header compiles without a project (val tests, examples without config.json). The natives-side caller is gated on CORE_HAS_SERIAL_BUSES, so the linker never asks for the symbol unless the dispatcher exists.

I2Cguide →

FunctionAccessDescription
core_i2c_write_byte_bus(uint8_t bus, uint8_t addr, uint16_t reg, uint8_t value)Tier 2Write a single byte to a register on a device on `bus`. Returns I2C_OK on success, I2C_NACK / I2C_ERROR on bus failure, or I2C_ERROR if `bus` isn't declared in config.json.
core_i2c_read_byte_bus(uint8_t bus, uint8_t addr, uint16_t reg)Tier 2Read a single byte from a register on a device on `bus`. Returns the byte value (0..255) on success, or -1 on any error (bus undeclared, NACK, timeout). The signed return lets DSL programs branch on `< 0` without an out-pointer.
core_i2c_probe_bus(uint8_t bus, uint8_t addr)Tier 2Check if a device responds at `addr` on `bus`. Returns 1 if the device ACKs, 0 on NACK / timeout / undeclared bus.
_core_i2c_timing(uint32_t speed_hz)Tier 1Resolve the TIMINGR value for a given speed using the compile-time I2C kernel clock (I2C_KERNEL_CLK_MHZ from core_config.h). Returns 0 if no pre-computed value exists.
core_i2c_init(core_i2c_t * h, I2C_TypeDef * instance, uint32_t speed_hz)Tier 1Initialize an I2C bus with automatic timing resolution. core_i2c_t bus; core_i2c_init(&bus, I2C1, I2C_400K); Resolves the TIMINGR value from the compile-time kernel clock. Enables FMP mode automatically when speed is I2C_1M.
core_i2c_init_cfg(core_i2c_t * h, I2C_TypeDef * instance, const hal_i2c_config_t * cfg)Tier 1Initialize I2C with explicit config struct (advanced). For most use cases, prefer core_i2c_init(h, instance, speed_hz).
core_i2c_write(core_i2c_t * h, uint8_t addr, const uint8_t * data, uint32_t len)Tier 1Write data to a 7-bit address device.
core_i2c_read(core_i2c_t * h, uint8_t addr, uint8_t * buf, uint32_t len)Tier 1Read data from a 7-bit address device.
core_i2c_write_reg(core_i2c_t * h, uint8_t addr, uint16_t reg, const uint8_t * data, uint32_t len)Tier 1Write to a device register (8 or 16-bit register address).
core_i2c_read_reg(core_i2c_t * h, uint8_t addr, uint16_t reg, uint8_t * buf, uint32_t len)Tier 1Read from a device register (repeated START).
core_i2c_write_byte(core_i2c_t * h, uint8_t addr, uint16_t reg, uint8_t value)Tier 1Write a single byte to a register.
core_i2c_read_byte(core_i2c_t * h, uint8_t addr, uint16_t reg, uint8_t * value)Tier 1Read a single byte from a register.
core_i2c_probe(core_i2c_t * h, uint8_t addr)Tier 1Check if a device responds at addr. Returns I2C_OK or I2C_NACK.
core_i2c_scan(core_i2c_t * h, uint8_t * found, uint8_t * count, uint8_t max_count)Tier 1Scan the I2C bus (0x08–0x77). Fills found[] with responding addresses.
core_i2c_handle_for_bus(uint8_t bus)Tier 1The I2C handle for a bus id declared in config.json, or NULL if the project doesn't declare that bus. Emitted per project by coregen into core_init.c (when the project declares any I2C bus); the *_bus helpers below resolve their handle through it. Forward-declared here rather than `#include "core_init.h"` so this header compiles without a project (val tests, examples without config.json). The natives-side caller is gated on CORE_HAS_I2C_BUSES, so the linker never asks for the symbol unless the dispatcher exists.
core_i2c_target_init(core_i2c_target_t * t, I2C_TypeDef * instance, uint8_t addr, uint32_t speed, uint8_t * regs, uint16_t n_regs, hal_i2c_target_cb_t cb, void * ctx)Tier 1Bring up an I2C peripheral as a read-only target at `addr`.
core_i2c_target_init_rw(core_i2c_target_t * t, I2C_TypeDef * instance, uint8_t addr, uint32_t speed, uint8_t * regs, uint16_t n_regs, uint16_t first, uint16_t count, hal_i2c_target_cb_t cb, void * ctx)Tier 1As core_i2c_target_init, but accepts host writes to the register range [first, first + count). Everything outside stays read-only.
core_i2c_target_deinit(core_i2c_target_t * t)Tier 1Stop answering on the bus.

SPIguide →

FunctionAccessDescription
core_spi_xfer_byte_bus(uint8_t bus, uint8_t cs_pad, uint8_t tx)Tier 2Single-byte full-duplex transfer over `bus`, with CS auto-managed around the call (asserted before, deasserted after). Returns the received byte (0..255) on success or -1 on any error (bus undeclared, cs_pad undefined, transfer timed out). The signed return lets DSL programs branch on `< 0` without an out-pointer. Most chip protocols pair two of these (write a register address, then read or write the value). Multi-byte sequences that need CS held across them — display init streams, audio frame transfers — still need Tier 1 with manual select/deselect.
core_spi_init(hal_spi_t * h, SPI_TypeDef * instance, const hal_spi_config_t * cfg)Tier 1Initialize SPI in master mode (8-bit frames).
core_spi_configure(hal_spi_t * h, const hal_spi_config_t * cfg)Tier 1Change prescaler, SPI mode or bit order, keeping the CS pad.
core_spi_sck_hz(const hal_spi_t * h)Tier 1The SCK frequency the handle is set to, in Hz.
core_spi_set_cs(hal_spi_t * h, uint8_t pad)Tier 1Assign a CS pin by tile pad number.
core_spi_select(hal_spi_t * h)Tier 1Assert CS. Everything until core_spi_deselect() is one transaction.
core_spi_deselect(hal_spi_t * h)Tier 1Deassert CS, ending the transaction.
core_spi_transfer(hal_spi_t * h, uint8_t tx)Tier 1Full-duplex single byte. CS untouched.
core_spi_exchange(hal_spi_t * h, const uint8_t * tx, uint8_t * rx, uint32_t len)Tier 1Full-duplex transfer of `len` bytes. CS untouched.
core_spi_write(hal_spi_t * h, const uint8_t * data, uint32_t len)Tier 1Write-only: send `len` bytes, discard what comes back. CS untouched.
core_spi_read(hal_spi_t * h, uint8_t * buf, uint32_t len)Tier 1Read-only: clock out the fill byte (0xFF) and capture `len` bytes. CS untouched.
core_spi_xfer(hal_spi_t * h, const uint8_t * tx, uint8_t * rx, uint32_t len)Tier 1One CS-framed full-duplex transaction: select, exchange, deselect.
core_spi_write_read(hal_spi_t * h, const uint8_t * tx, uint32_t tx_len, uint8_t * rx, uint32_t rx_len)Tier 1One CS-framed command + data transaction.
core_spi_exchange_dma(hal_spi_t * h, const uint8_t * tx, uint8_t * rx, uint32_t len)Tier 1Full-duplex DMA transfer, blocking until the last frame is off the bus. CS untouched.
core_spi_xfer_dma(hal_spi_t * h, const uint8_t * tx, uint8_t * rx, uint32_t len, hal_callback_t cb, void * ctx)Tier 1Start a full-duplex DMA transfer and return at once.
core_spi_dma_wait(hal_spi_t * h)Tier 1Wait for a core_spi_xfer_dma() transfer to finish (bounded).
core_spi_busy(hal_spi_t * h)Tier 1Whether a DMA transfer is in progress on this handle.
core_spi_handle_for_bus(uint8_t bus)Tier 1The SPI handle for a bus id declared in config.json, or NULL if the project doesn't declare that bus. Emitted per project by coregen into core_init.c (when the project declares any SPI bus); the *_bus helpers below resolve their handle through it. Forward-declared here rather than `#include "core_init.h"` so this header compiles without a project (val tests, examples without config.json). The natives-side caller is gated on CORE_HAS_SPI_BUSES, so the linker never asks for the symbol unless the dispatcher exists.

Timers & PWMguide →

FunctionAccessDescription
core_timer_init_freq(core_timer_t * h, TIM_TypeDef * instance, uint32_t freq_hz)Tier 1Initialize a timer at a given overflow frequency. Use for PWM output and periodic tick — the frequency is how often the counter wraps (= the PWM frequency). core_timer_init_freq(&t, TIM2, 1000); // overflows at 1 kHz
core_timer_set_trgo(core_timer_t * h, uint32_t mms)Tier 1Route an internal timer event to TRGO so another peripheral can be paced by it, with no pin, no channel and no interrupt involved. LL_TIM_MMS_UPDATE is the periodic-pacer case: every counter overflow emits a trigger. Pair it with core_adc_set_trigger() to run the ADC at an exact rate instead of free-running. core_timer_init_freq(&t, TIM2, 800); core_timer_set_trgo(&t, LL_TIM_MMS_UPDATE); core_timer_start(&t);
core_timer_init_tick(core_timer_t * h, TIM_TypeDef * instance, uint32_t tick_hz)Tier 1Initialize a timer at a given tick rate, free-running to max count. Use for input capture — the tick rate sets the measurement resolution, and the counter runs as long as possible before wrapping (0xFFFF for 16-bit, 0xFFFFFFFF for 32-bit TIM2). core_timer_init_tick(&t, TIM2, 1000000); // 1 us per tick core_timer_capture_init(&t, 1); core_timer_start(&t);
core_timer_start(core_timer_t * h)Tier 1Start the timer counter.
core_timer_stop(core_timer_t * h)Tier 1Stop the timer counter.
core_timer_set_freq(core_timer_t * h, uint32_t freq_hz)Tier 1Change the timer frequency (recalculates PSC/ARR).
core_timer_pwm_set(core_timer_t * h, uint8_t channel, uint16_t duty_permil)Tier 1Set PWM duty cycle for a channel. channel: 1–4 duty_permil: 0–1000 (0 = off, 500 = 50%, 1000 = always on)
core_timer_pwm_set_pad(core_timer_t * h, uint8_t pad, uint16_t duty_permil)Tier 1Set PWM duty cycle by pad number (requires coregen: only defined when the project's config.json binds a timer to a pad). Resolves the channel from the pad's timer assignment; pads without a timer are ignored.
core_timer_capture_init(core_timer_t * h, uint8_t channel)Tier 1Configure a channel for input capture (rising edge). The timer must already be initialized with core_timer_init().
core_timer_capture_read(core_timer_t * h, uint8_t channel)Tier 1Read the last captured value from a channel.
core_timer_enable_tick(core_timer_t * h, core_callback_t cb, void * ctx)Tier 1Enable periodic tick on an already-initialized timer. Does NOT touch PSC/ARR — the timer keeps its existing timebase. The callback fires on each counter overflow at the timer's frequency. Typical pattern: core_timer_init(&t, TIM2, 1000); // 1 kHz timebase core_timer_pwm_set(&t, 1, 500); // CH1 = 50% PWM (permil) core_timer_enable_tick(&t, on_tick, NULL); // also fire ISR at 1 kHz core_timer_start(&t);
core_timer_disable_tick(core_timer_t * h)Tier 1Disable the tick callback (clears UIE, keeps timer running).
core_tick_init(core_timer_t * h, TIM_TypeDef * instance, uint32_t period_us, core_callback_t cb, void * ctx)Tier 1Convenience: initialize a timer as a tick-only source. Sets up the timebase AND enables the update interrupt. Use this when the timer's only job is a periodic callback. core_tick_init(&t, TIM3, 500000, on_tick, NULL); // 2 Hz core_timer_start(&t);
core_pwm_duty(uint8_t pad, uint16_t duty_permil)Tier 2Set PWM duty cycle on a pad. Timer handle resolved from config.json.
core_pwm_init(core_timer_t * h, TIM_TypeDef * instance, uint32_t freq_hz)Tier 1Initialize a timer for PWM output at the given frequency. Clock is auto-resolved from SYSCLK_HZ (core_config.h).
core_pwm_init_clk(core_timer_t * h, TIM_TypeDef * instance, uint32_t pclk_hz, uint32_t freq_hz)Tier 1
core_pwm_set(core_timer_t * h, uint8_t channel, uint16_t duty_permil)Tier 1Set PWM duty cycle for a channel. channel: 1–4 duty_permil: 0–1000 (0 = off, 500 = 50%, 1000 = 100%)
core_pwm_set_freq(core_timer_t * h, uint32_t freq_hz)Tier 1Change PWM frequency (recalculates PSC/ARR, resets all channel duties).
core_pwm_start(core_timer_t * h)Tier 1Start the PWM timer.
core_pwm_stop(core_timer_t * h)Tier 1Stop the PWM timer.
core_pwm_init_pad(core_timer_t * h, uint8_t pad, uint32_t freq_hz)Tier 1Initialize PWM on a pad. Timer instance resolved from config.json.
core_pwm_set_pad(core_timer_t * h, uint8_t pad, uint16_t duty_permil)Tier 1Set PWM duty on a pad (0–1000 permil).
core_pwm_timer_for_pad(uint8_t pad)Tier 1The timer driving a pad. Emitted per project by coregen into core_init.c when any TIM<n> pad is configured.
core_every_us(core_timer_t * h, TIM_TypeDef * instance, uint32_t period_us, hal_callback_t cb, void * ctx)Tier 1Configure a periodic callback at a fixed interval. period_us: interval in microseconds (1 – 1000000) cb: callback function (called from ISR context!) ctx: user context passed to callback Clock is auto-resolved from SYSCLK_HZ (core_config.h).
core_every_us_clk(core_timer_t * h, TIM_TypeDef * instance, uint32_t pclk_hz, uint32_t period_us, hal_callback_t cb, void * ctx)Tier 1
core_every_start(core_timer_t * h)Tier 1Start the periodic timer.
core_every_stop(core_timer_t * h)Tier 1Stop the periodic timer.

Stepper (STEP/DIR)guide →

FunctionAccessDescription
core_stepper_init(core_stepper_t * h, uint8_t step_pad, uint8_t dir_pad)Tier 1Bind a stepper axis to a STEP pad (timer output) and a DIR pad. The timer and channel come from the pad's TIMx.y assignment in config.json, which is also what routes the pin to the timer. Loads conservative defaults: 1000 steps/s cruise, 100 steps/s start, 4000 steps/s^2 ramp, 8 us pulses. The timer is left stopped until a move. Do not share the timer with a PWM output — the module rewrites its period on every step.
core_stepper_init_ch(core_stepper_t * h, TIM_TypeDef * instance, uint8_t channel, uint8_t step_pad, uint8_t dir_pad)Tier 1Bind an axis with an explicit timer instance and channel (no coregen lookup). The caller must have configured the STEP pad's alternate function for that channel. Everything else as core_stepper_init().
core_stepper_set_enable_pad(core_stepper_t * h, uint8_t en_pad, bool active_low)Tier 1Add an ENABLE output. The pad is driven to its disabled level immediately; call core_stepper_enable() to power the driver. Pass pad 0 to remove it.
core_stepper_enable(core_stepper_t * h, bool on)Tier 1Drive the ENABLE pad. No effect without core_stepper_set_enable_pad(). Motion is not interlocked: halt before disabling if you care where the rotor ends up.
core_stepper_set_polarity(core_stepper_t * h, bool step_active_low, bool dir_invert)Tier 1Set signal polarities. Call while idle.
core_stepper_set_pulse_us(core_stepper_t * h, uint32_t pulse_us)Tier 1Set the STEP pulse width; the low time between pulses is kept at least as long, which also bounds DIR setup. 8 us (default) satisfies the DM320T's 7.5 us; a DRV8428 is happy with 1 us. The maximum step rate is 1 / (2 * pulse_us).
core_stepper_set_speed(core_stepper_t * h, uint32_t steps_per_s)Tier 1Set the cruise rate for position moves and the cap for run(). Takes effect at the next step; a move in flight ramps to the new value.
core_stepper_set_accel(core_stepper_t * h, uint32_t steps_per_s2)Tier 1Set the acceleration used for every ramp, or 0 to switch instantly between the start rate and full speed (fine for small, unloaded motors at low rates; expect stalls otherwise).
core_stepper_set_min_speed(core_stepper_t * h, uint32_t steps_per_s)Tier 1Set the rate a ramp starts from and stops at. Steppers can start instantly at a few hundred full steps per second; starting from a crawl only wastes time. Clamped to at least 1 (16 on a 16-bit timer).
core_stepper_move(core_stepper_t * h, int32_t steps)Tier 1Move a signed number of microsteps relative to the current target (so two quick calls of +160 travel 320). Retargets a move in flight; a reversal decelerates to the start rate before flipping DIR.
core_stepper_move_to(core_stepper_t * h, int32_t position)Tier 1Move to an absolute microstep position.
core_stepper_run(core_stepper_t * h, int32_t steps_per_s)Tier 1Run continuously at a signed rate, ramping from the current speed. Rate 0 decelerates to a stop (same as core_stepper_stop()). The magnitude is capped at the cruise rate from core_stepper_set_speed().
core_stepper_stop(core_stepper_t * h)Tier 1Decelerate to a stop using the configured acceleration. Position continues to count during the ramp. Idempotent.
core_stepper_halt(core_stepper_t * h)Tier 1Stop instantly: timer off, STEP forced to idle. A pulse whose rising edge the driver has already seen is counted. A loaded motor at speed will lose steps; the position counter reflects the pulses sent.
core_stepper_busy(const core_stepper_t * h)Tier 1true while pulses are being generated (including a ramp to zero).
core_stepper_state(const core_stepper_t * h)Tier 1Current motion state.
core_stepper_position(const core_stepper_t * h)Tier 1Current signed microstep position (pulses actually issued).
core_stepper_set_position(core_stepper_t * h, int32_t position)Tier 1Redefine the current position without moving (homing). Only while idle; the target follows so the next move() is relative to it.
core_stepper_target(const core_stepper_t * h)Tier 1Target position of the current or last move.
core_stepper_speed(const core_stepper_t * h)Tier 1Current signed step rate.
core_stepper_stop_distance(const core_stepper_t * h, uint32_t steps_per_s)Tier 1Microsteps needed to decelerate from `steps_per_s` to the start rate at the configured acceleration. Useful for planning where a run() will stop, e.g. to land on a pocket boundary.

Analog (ADC / DAC)guide →

FunctionAccessDescription
core_adc_read_pad(uint8_t pad)Tier 2Read a pad as raw ADC counts (0–4095 at 12-bit resolution).
core_adc_read_mv_pad(uint8_t pad)Tier 2Read a pad as calibrated millivolts (uses VREFINT for per-chip accuracy).
core_adc_temp_decidegc(void)Tier 2Die temperature in tenths of deg C (e.g. 253 = 25.3 C). Dispatches to the default ADC instance.
core_adc_vdd_mv(void)Tier 2VDD supply voltage in millivolts (via VREFINT). Dispatches to the default ADC instance.
core_adc_init(core_adc_t * adc, uint32_t resolution)Tier 1Initialise the ADC at the given resolution.
core_adc_add(core_adc_t * adc, uint8_t pad, uint32_t samp)Tier 1Register a pad as an ADC input with the given sampling speed.
core_adc_read(core_adc_t * adc, uint8_t pad)Tier 1Single-shot read — returns raw ADC count.
core_adc_read_mv(core_adc_t * adc, uint8_t pad)Tier 1Single-shot read — returns calibrated millivolts.
core_adc_temp(core_adc_t * adc)Tier 1Die temperature in tenths of deg C (e.g. 253 = 25.3 C).
core_adc_vdd(core_adc_t * adc)Tier 1Actual VDD supply voltage in millivolts via VREFINT.
core_adc_start_dma(core_adc_t * adc, uint16_t * buf, uint16_t len, hal_callback_t cb, void * ctx)Tier 1Start continuous conversion with DMA circular buffer.
core_adc_stop_dma(core_adc_t * adc)Tier 1Stop continuous DMA conversion.
core_adc_dma_read(core_adc_t * adc, uint8_t pad)Tier 1Read most recent DMA result for a pad.
core_adc_dma_read_mv(core_adc_t * adc, uint8_t pad)Tier 1Read most recent DMA result for a pad, in calibrated millivolts. Prime VDDA before starting DMA (call core_adc_vdd(adc) once), since measuring VREFINT needs the regular sequence that DMA owns.
core_adc_raw_to_mv(core_adc_t * adc, uint16_t raw)Tier 1Convert a raw count from a DMA buffer to millivolts.
core_adc_set_trigger(core_adc_t * adc, uint8_t extsel, uint32_t edge)Tier 1Pace DMA conversions from a hardware trigger instead of free-running. Call before core_adc_start_dma. See hal_adc_set_trigger for why this matters to any slow output rate: it is what makes a DMA ring span the whole output period, turning the average into a real anti-alias filter instead of a burst average. core_timer_init_freq(&t, TIM2, 800); core_timer_set_trgo(&t, LL_TIM_MMS_UPDATE); core_adc_set_trigger(adc, LL_ADC_L0_TRG_TIM2_TRGO, ADC_TRIG_RISING); core_adc_start_dma(adc, buf, len, 0, 0); core_timer_start(&t);
core_adc_dma_slot(core_adc_t * adc, uint8_t pad)Tier 1Buffer slot a pad occupies in one DMA scan (-1 if not registered). Use the stride when the buffer holds several scans for averaging.
core_dac_init(void)Tier 2Initialize the DAC (clock, GPIO, peripheral). Call once from `on start` before any writes.
core_dac_write(uint16_t val)Tier 2Write a raw 12-bit value. Output = val / 4095 × VREF+.
core_dac_write_mv(uint16_t mv)Tier 2Write a voltage in millivolts.
core_dac_read(void)Tier 2Read back the current DAC output register value (12-bit).

Audio (PDM mic)guide →

FunctionAccessDescription
core_audio_init(core_audio_t * a, uint32_t kernel_clk_hz, uint32_t pcm_rate_hz, uint8_t data_line, uint8_t clock_line, uint8_t cic_order, uint8_t gain_shift)Tier 1Configure the mic: SAI PDM block + decimator (capture not started).
core_audio_start(core_audio_t * a, GPDMA_Channel_TypeDef * ch, uint8_t * pdm_buf, uint32_t pdm_len, int16_t * pcm_buf, core_audio_pcm_cb on_pcm, void * user_ctx)Tier 1Start continuous capture; `on_pcm` fires per half-buffer with PCM.
core_audio_stop(core_audio_t * a)Tier 1Stop capture.
core_audio_irq(core_audio_t * a)Tier 1Route the capture channel's GPDMA IRQ here.
core_pdm_init(core_pdm_cic_t * st, uint8_t order, uint16_t decimation, uint8_t gain_shift, uint8_t lsb_first)Tier 1Initialise a CIC decimator.
core_pdm_process(core_pdm_cic_t * st, const uint8_t * pdm, uint32_t nbytes, int16_t * out)Tier 1Decimate a block of packed PDM bits into PCM samples.

Powerguide →

FunctionAccessDescription
core_sleep(void)Tier 2Sleep until any interrupt (CPU stopped, peripherals running).
core_stop_for(uint32_t seconds)Tier 2Enter Stop mode for a number of seconds, then wake and restore clocks. Uses the RTC wakeup timer (LSI). Returns after wake with PLL + SysTick restored; core_millis() advances by the time slept, as the RTC measured it. If the watchdog is running, sleeps in chunks of half its timeout and feeds it in between. Core.ST.L4 with a USB host awake on the bus: waits in Sleep mode so the host can still reach it (see the USB note at the top).
core_woke_from_standby(void)Tier 2Returns 1 if the MCU woke from Standby. The flag survives later resets until core_clear_standby_flag() — call that once you've handled the wake.
core_clock_init(void)Tier 1Bring up the clock tree for the project's `clock` level (oscillator, PLL, flash wait states, bus prescalers) and start SysTick. Generated per project by coregen into core_init.c and called by core_init(); call it again only to restore the clocks by hand (core_stop_for already does after a wake).
core_stop_until_on_change_timeout(uint8_t pad, uint32_t edge, uint32_t timeout_ms)Tier 1Enter Stop mode until a GPIO edge on the given pad, or until `timeout_ms` has passed (0 = no timeout). Configures the pad as input, arms its EXTI, enters Stop, and restores clocks on wake. If the watchdog is running, wakes every half timeout to feed it and goes back to sleep. Core.ST.L4 with a USB host awake on the bus: waits in Sleep mode (see the USB note at the top). Already at the wake level: EXTI latches only edges that happen after it is armed, so a line that is already at its wake level — a sensor INT held low until serviced, for EDGE_FALLING — would never wake the Core. After arming, this reads the pad and returns 1 at once if it is already low (EDGE_FALLING) or high (EDGE_RISING). EDGE_BOTH always waits for a change.
core_stop_until_on_change(uint8_t pad, uint32_t edge)Tier 1Enter Stop mode until a GPIO edge occurs on the given pad (no timeout). Returns right away if the pad can't take an edge interrupt, or if it is already at the level the edge wakes on (see core_stop_until_on_change_timeout()). If the watchdog is running, wakes every half timeout to feed it and goes back to sleep.
core_standby_for(uint32_t seconds)Tier 1Enter Standby mode with RTC wakeup after the given seconds. On success it does not return — the MCU resets on wake. Check core_woke_from_standby() at the top of main() to detect a Standby wake. Watchdog: the IWDG keeps counting through Standby and nothing feeds it until main() runs again, and Standby can't be split into fed chunks. So while the watchdog is running this refuses — returns HAL_ERROR without sleeping — unless seconds is at most half the watchdog timeout (2 s with the default 5 s watchdog). Use core_stop_for() for longer sleeps. (Core.ST.H5: no check.)
core_standby_until_on_change(uint8_t pad, uint32_t edge)Tier 1Enter Standby mode until a GPIO edge on the given pad (via WKUP pin). Does not return — MCU resets on wake. Not all pads support WKUP; returns without entering Standby if the pad has no WKUP capability, or if the watchdog is running (it would reset the Core long before most edges). On Core.ST.L4.2: pad 8 (PA0 = WKUP1) and pad 7 (PA2 = WKUP4).
core_stop(void)Tier 1Enter Stop mode (caller manages wakeup source + clock recovery). A running watchdog keeps counting and is not fed: wake within its timeout. On the WBA the caller also owns the Stop 1 wait-state/HDIV5 rules (RM0493 §11.7.7).
core_standby(void)Tier 1Enter Standby (caller manages wakeup source). Does not return. A running watchdog keeps counting through Standby and resets the Core at its timeout.
core_clear_standby_flag(void)Tier 1Clear the Standby wake flag. Call after core_woke_from_standby() returns 1.
core_watchdog_start_seconds(uint32_t seconds)Tier 1Start the independent watchdog with a timeout in seconds (convenience). For finer control use core_watchdog_start() from core_watchdog.h which accepts milliseconds.
core_rtc_init(void)Tier 2Initialize the RTC using LSI (internal RC, ~32 kHz; ~37 kHz on Core.ST.L0, scaled so a second is still ~1 s). Call once from `on start` before setting time, date, or alarms. For LSE, call ll_rtc_init(1) directly in hand-written C (Core.ST.L0 has no LSE and stays on LSI).
core_rtc_set_time(uint8_t h, uint8_t m, uint8_t s)Tier 2Set the time (24h format).
core_rtc_set_date(uint8_t y, uint8_t mo, uint8_t d, uint8_t wd)Tier 2Set the date.
core_rtc_wakeup(uint32_t seconds)Tier 2Configure a periodic wakeup timer.
core_rtc_wakeup_stop(void)Tier 2Disable the periodic wakeup timer.
core_rtc_set_alarm(uint8_t hours, uint8_t minutes, uint8_t seconds)Tier 2Set Alarm A to trigger at a specific time. Pass 0xFF for hours, minutes, or seconds to ignore that field. The alarm fires when all non-masked fields match the RTC time.
core_rtc_clear_alarm(void)Tier 2Clear the alarm (disable Alarm A).
core_rtc_alarm_fired(void)Tier 2Check if the alarm has fired (poll mode). Clears the flag on read.
core_rtc_get_time(uint8_t * h, uint8_t * m, uint8_t * s)Tier 1Read the current time.
core_rtc_get_date(uint8_t * y, uint8_t * mo, uint8_t * d, uint8_t * wd)Tier 1Read the current date.
core_backup_read(uint8_t index)Tier 2Read a backup register.
core_backup_write(uint8_t index, uint32_t value)Tier 2Write a backup register. Backup domain write access is enabled automatically.
_core_backup_ensure_clk(void)Tier 1Ensure the backup registers are reachable. L0: RTC_BKPxR live inside the RTC (RM0377 §22.7.20), so the RTC clock must be selected, enabled and running (LSI; never the LSE here). L4 (L422): TAMP_BKPxR (RM0394 §36.6.8) on the RTC APB clock; the RTC kernel clock is brought up too, as before, in case nothing else has. WBA: TAMP_BKPxR (RM0493 §37.6.18) need RCC_APB7ENR.RTCAPBEN, which is off at reset — without it TAMP read 0 and ignored writes unless the BLE stack happened to have set it. H5: TAMP on RCC_APB3ENR.RTCAPBEN. All of them need PWR + DBP for writes.

Storage & IDguide →

FunctionAccessDescription
core_nvm_size(void)Tier 2Returns the total NVM size in bytes for this Core.
core_nvm_read_byte(uint32_t offset)Tier 2Read a single byte from NVM at `offset`. Returns the byte (0..255) on success or -1 on any error (offset out of range, NVM disabled). A byte never written reads 255 (0xFF) on Core.ST.L4 / W5 and 0 on Core.ST.L0. The signed return lets DSL programs branch on `< 0` without an out-pointer.
core_nvm_write_byte(uint32_t offset, uint8_t value)Tier 2Write a single byte to NVM at `offset`. Returns 1 on success or -1 on any error (offset out of range, flash error, no NVM on this Core). Each call is one flash record on Core.ST.L4 / W5: fine for a setting or a boot counter, wasteful in a tight loop (see core_nvm.h on wear).
core_nvm_read(uint32_t offset, void * buf, uint32_t len)Tier 1Read bytes from NVM. Bytes never written read as CORE_NVM_ERASED (0xFF on Core.ST.L4 / W5, 0 on Core.ST.L0). Core.ST.H5 has no NVM yet: this always returns CORE_NVM_ERR_RANGE there.
core_nvm_write(uint32_t offset, const void * data, uint32_t len)Tier 1Write bytes to NVM. On Core.ST.L4 / W5 (1 KB, flash-emulated) a write is atomic: after a reset or power loss the range reads all old or all new, and the data survives reflashing. Most writes take well under a millisecond; about one small write in a hundred (L4; one in 500 on the W5) compacts the store, which erases a flash page and stalls the Core.ST.L4 for ~22 ms. Core.ST.L0 writes its EEPROM byte by byte (~3.2 ms each). Core.ST.H5 has no NVM yet.
core_nvm_erase_all(void)Tier 1Erase the whole NVM region: every byte reads CORE_NVM_ERASED afterwards. Core.ST.L4 / W5: one page erase, or nothing if the region is already empty. Core.ST.L0: clears the EEPROM word by word (up to ~0.4 s; words already clear are skipped).
core_otp_size(void)Tier 2Total OTP size in bytes for this Core (0 where unavailable).
core_otp_slot_count(void)Tier 2Number of write-once quad-word slots (CORE_OTP_SIZE / 16).
core_otp_slot_is_blank(uint32_t slot)Tier 2Return 1 if `slot` is entirely erased (all 0xFF), 0 if any bit is programmed, or -1 if the slot index is out of range / OTP unavailable. A blank slot is programmable; a non-blank slot is not (write-once).
core_otp_slot_addr(uint32_t slot)Tier 1Absolute address of a slot (no bounds check).
core_otp_read(uint32_t offset, void * buf, uint32_t len)Tier 1Read bytes from OTP into `buf`. Memory-mapped load; no unlock needed. Returns 0 on success, -1 if the range is out of bounds or OTP is unavailable on this Core.
core_otp_program_slot(uint32_t slot, const void * rec)Tier 1Program one 16-byte quad-word slot (write-once) and verify the read-back. IRREVERSIBLE. Refuses a slot that is not blank (returns -2) so a second write can't corrupt an existing record. On WBA55 this unlocks flash, issues a single 128-bit quad-word program, re-locks, and confirms the stored bytes match `rec`. There is no retry and no undo — callers should treat a failure as "advance to the next slot", not "try again here". slot: 0 .. CORE_OTP_SLOT_COUNT-1 rec: pointer to exactly CORE_OTP_SLOT_SIZE (16) bytes. Returns 0 on success, -1 on range/program/verify error, -2 if the slot is not blank, -3 if OTP programming is unavailable on this Core. Deliberately NOT `@studio expose`d: a destructive, irreversible burn does not belong in the DSL palette. It is escape-to-C only (see @studio unsupported below).
core_uid_read(uint32_t out[3])Tier 1Read the 96-bit unique device ID as three 32-bit words.
core_uid_hash(void)Tier 1Fold the full 96-bit ID into a single stable 32-bit value (the three words XORed together). Better mixed than any single word — use it to derive short tokens (e.g. a 4-hex-digit name suffix) where the raw low bytes might be correlated across a manufacturing batch.
core_uid_hex(char * buf, uint16_t buflen)Tier 1Format the full 96-bit ID as an uppercase hex string (24 hex characters, word 0 first, most-significant nibble first within each word) plus a NUL terminator. The canonical form for a device serial number.

Securityguide →

FunctionAccessDescription
core_rng_read(void)Tier 2Read a single 32-bit random value (blocking). Returns 0 on timeout — check core_rng_error() if this happens.
core_rng_init(void)Tier 1Initialize the hardware RNG. Enables the peripheral clock, configures the RNG, and waits for the first random number to be ready. On Core.ST.L4: requires HSI48 to be running (auto-enabled if USB is used, otherwise call ll_rcc_hsi48_enable() first).
core_rng_fill(uint32_t * buf, uint32_t count)Tier 1Fill a buffer with random 32-bit values (blocking).
core_rng_error(void)Tier 1Check if the RNG has a seed error (entropy source failure).
core_rng_deinit(void)Tier 1Power down the RNG peripheral.

USBguide →

FunctionAccessDescription
core_usb_print(const char * s)Tier 2Print a string followed by a newline. Thin wrapper for DSL-style callers.
core_usb_print_int(int v)Tier 2Print a signed integer followed by a newline.
core_usb_print_float(double v)Tier 2Print a double with a newline. %g trims trailing zeros for readability.
core_usb_print_bool(int v)Tier 2Print "true" / "false" followed by a newline.
core_usb_init(void)Tier 1Initialize USB CDC. Device appears as /dev/tty.usbmodem* on the host.
core_usb_connected(void)Tier 1Returns 1 if a host terminal is connected (DTR set).
core_usb_wait_host(uint32_t timeout_ms)Tier 1Wait up to `timeout_ms` for a host terminal to open the port (DTR set). Feeds the watchdog while it waits. Not needed just to see early output: on Core.ST.L4 text printed before the port opens is kept (up to HAL_USB_CDC_TX_QUEUE_SIZE bytes) and sent when it does.
core_usb_write(const uint8_t * buf, uint16_t len)Tier 1Transmit data: queued, never waits long (see hal_usb_cdc_write); returns bytes queued, -1 before init.
core_usb_try_write(const uint8_t * buf, uint16_t len)Tier 1Transmit without waiting: queues the whole buffer or none of it. Returns len if queued, 0 if there is no room right now (offer it again later), -1 if no terminal is connected. Main loop only.
core_usb_on_receive(hal_usb_cdc_rx_cb_t cb, void * ctx)Tier 1Set a callback for received data. Called from USB ISR. When set, data is NOT buffered for polling reads.
core_usb_available(void)Tier 1Returns the number of bytes available to read (ring buffer mode).
core_usb_getc(void)Tier 1Read a single byte (blocking — waits for data).
core_usb_read(uint8_t * buf, uint16_t max)Tier 1Read available bytes into buf (non-blocking). Returns bytes read.
core_usb_try_read(uint8_t * byte)Tier 1Non-blocking single byte read. Returns 1 if a byte was read, 0 if empty.
core_usb_hid_send(const uint8_t * buf, uint16_t len)Tier 1Send a HID report (up to 64 bytes, zero-padded automatically). Blocking — waits for the previous report to be read by the host. Returns bytes of user data sent, or -1 if USB not configured.
core_usb_hid_set_rx_callback(hal_usb_hid_rx_cb_t cb, void * ctx)Tier 1Register a callback for inbound HID reports (host -> device). Fires from the USB ISR with one report per call (up to 64 bytes), delivered via the EP3 OUT interrupt endpoint or HID SET_REPORT. Pass NULL to disable; unhandled reports are dropped.

BLEguide →

FunctionAccessDescription
core_ble_set_services(void)Tier 1Register a service builder function. Called before core_ble_init(). The builder is invoked during init after the GATT server is ready.
core_ble_add_services(void)Tier 1Register an ADDITIONAL service builder, run after the application's own. For SDK modules that bring a GATT service of their own (core_scope's Studio Link) without taking over core_ble_set_services(), which the application — or coregen's generated contract — owns. Call before core_ble_init(). Registering the same builder twice is harmless. Returns 0, or -1 if the slots are full or the stack has already started.
core_ble_init(void)Tier 1Initialize the BLE stack. Call once after core_init().
core_ble_advertise(const char * name)Tier 1Start advertising. Call after init + at least one core_ble_process().
core_ble_stop_advertise(void)Tier 1Stop advertising.
core_ble_process(void)Tier 1Process BLE events. Call continuously from main loop.
core_ble_add_service(const char * name)Tier 1Add a GATT service. Returns a handle for adding characteristics. The UUID is auto-assigned SEQUENTIALLY by registration order (0000B000-…, 0000B100-…, …). Convenient, but the UUIDs shift if you reorder or insert services — so for a contract shared with client apps, prefer core_ble_add_service_id() to pin a stable, order-independent UUID.
core_ble_add_service_id(const char * name, uint16_t id)Tier 1Add a GATT service with an EXPLICIT 16-bit ID. The full UUID is 0000<id>-8E22-4541-9D4C-21EDAE82ED19. Pinning the ID makes the GATT contract independent of registration order — the recommended path when the service map is a source of truth shared with phone / desktop client apps.
core_ble_add_char(core_ble_svc_t svc, const char * name, uint8_t access, uint8_t type, core_ble_write_cb on_write, void * ctx)Tier 1Add a characteristic to a service.
core_ble_add_char_id(core_ble_svc_t svc, const char * name, uint16_t id, uint8_t access, uint8_t type, core_ble_write_cb on_write, void * ctx)Tier 1Add a characteristic with an EXPLICIT 16-bit ID (0000<id>-8E22-…), the order-independent counterpart to core_ble_add_char(). Use for the stable contract shared with client apps.
core_ble_add_service_sig(const char * name, uint16_t uuid16)Tier 1Add a SIG-adopted service by its 16-bit Bluetooth UUID (e.g. 0x180F Battery Service, 0x180A Device Information). Use adopted services for standardised profiles so generic clients and the host OS recognise them; use the _id variants for custom application-specific data.
core_ble_add_char_sig(core_ble_svc_t svc, const char * name, uint16_t uuid16, uint8_t access, uint8_t type, core_ble_write_cb on_write, void * ctx)Tier 1Add a SIG-adopted characteristic by its 16-bit Bluetooth UUID (e.g. 0x2A19 Battery Level, 0x2A29 Manufacturer Name) to a service.
core_ble_set_value(core_ble_char_t ch, const void * data, uint16_t len)Tier 1Update a characteristic's value. For readable characteristics, this is what the central will read. For notify characteristics, call core_ble_notify() after to push the update.
core_ble_notify(core_ble_char_t ch)Tier 1Send a notification to the connected central. The central must have enabled notifications (CCCD) for this to work. Sends the current value set by core_ble_set_value().
core_ble_subscribed(core_ble_char_t ch)Tier 1Has a client subscribed to notifications on this characteristic?
core_ble_connected(void)Tier 1Returns 1 if a central is connected.
core_ble_on_connect(void * ctx)Tier 1Set callback for connection events.
core_ble_on_disconnect(void * ctx)Tier 1Set callback for disconnection events.
core_ble_set_tx_power(uint8_t level)Tier 1TX power: 0=low(-20dBm), 1=medium(0dBm), 2=high(+10dBm). Default: 1.
core_ble_set_adv_interval(uint16_t min_ms, uint16_t max_ms)Tier 1Advertising interval in ms (20-10240). Default: 100/150.
core_ble_set_conn_params(uint16_t min_ms, uint16_t max_ms, uint16_t latency, uint16_t timeout_ms)Tier 1Request a preferred connection parameter set from the central. The central ultimately owns the connection timing, but a peripheral can ask for parameters that suit its traffic. After each connection the SDK sends an L2CAP update request (retrying until the stack accepts it, since the link is busy with pairing/discovery right after connecting). May also be called while connected to re-request — e.g. tighten the interval while streaming, relax it when idle. For Apple hosts, keep within their guidelines: interval_min >= 15 ms, interval_max >= interval_min + 15 ms, interval_max * (latency + 1) <= 2 s, and timeout in 2000..6000 ms. A short interval lowers latency for high-rate notifications at the cost of power; latency > 0 saves power when the peripheral often has nothing to send.
core_ble_enable_pairing(void)Tier 1Enable OS-level pairing + bonding (Just Works). When enabled, every characteristic is registered behind an encrypted link, so on first access the host runs its pairing flow (a "Pair?" prompt on most OSes; silent for Just Works on macOS). Keys are persisted in flash NVM, so the bond survives resets — the host doesn't re-pair on the next connection and the device stays listed in OS Bluetooth settings. (Reconnect itself is the central's choice; the peripheral simply re-advertises after a drop.) Call before core_ble_init(). Default: disabled (characteristics open, no pairing). Note that once enabled, *all* clients must pair to read/write.

Scope (live streaming)guide →

FunctionAccessDescription
core_scope_init(void)Tier 1Start the module on the Core's default link.
core_scope_set_link(const core_scope_link_t * link)Tier 1Stream over a different link than the default.
core_scope_add(const char * name, const volatile void * ptr, core_scope_type_t type)Tier 1Register one variable as a channel.
core_scope_add_array(const char * name, const volatile void * ptr, core_scope_type_t type, uint8_t count)Tier 1Register a fixed array as channels `name[0]` .. `name[count-1]`.
core_scope_set_interval_ms(uint32_t ms)Tier 1Limit core_scope_update() to one sample per `ms` milliseconds.
core_scope_declare_rate_hz(uint32_t hz)Tier 1Promise that samples are taken at exactly this rate.
core_scope_declare_rate_millihertz(uint32_t millihertz)Tier 1As core_scope_declare_rate_hz(), in millihertz — for rates that are not a whole number of hertz (an IMU at 416.667 Hz = 416667).
core_scope_sample(void)Tier 1Snapshot the registered variables. ISR-safe.
core_scope_pump(void)Tier 1Frame the pending samples and hand them to the link. Main loop.
core_scope_update(void)Tier 1core_scope_sample() + core_scope_pump(), honoring the interval gate. The one call a simple main loop needs.
core_scope_enable(int on)Tier 1Pause or resume at run time (a debug button, a BLE command).
core_scope_active(void)Tier 1Is a host listening right now?
core_scope_dropped(void)Tier 1Samples dropped since boot because the ring was full.