Analog (ADC / DAC)

Overview

The ADC is a 12-bit SAR converter (counts 0–4095). You can read a pad as raw counts, or as millivolts — the latter uses the factory VREFINT calibration so the reading is supply-independent. The Tier 2 pad calls own ADC1 and read by tile pad number; the Tier 1 handle API gives you resolution, sampling speed, and DMA.

Reading inputs

The shortest path is the Tier 2 pad read — coregen has already set the pad to analog. For full control (resolution, sampling speed) use the Tier 1 handle:

#include "core.h"

// Tier 2 — pad declared analog in config.json:
uint16_t raw = core_adc_read_pad(8);
uint32_t mv  = core_adc_read_mv_pad(8);

// Tier 1 — explicit handle:
core_adc_t adc;
core_adc_init(&adc, ADC_12BIT);
core_adc_add(&adc, 8, SAMP_MED);
uint16_t r = core_adc_read(&adc, 8);
uint32_t v = core_adc_read_mv(&adc, 8);

Temperature & supply

Two internal channels need no pad: the die temperature sensor and the supply rail (via VREFINT). The Tier 2 calls return tenths of a degree and millivolts:

int32_t  decidegc = core_adc_temp_decidegc();   // e.g. 234 = 23.4 °C
uint32_t vdd_mv   = core_adc_vdd_mv();          // measured supply

DAC output

On the H5 Core, the DAC drives a fixed voltage out. Init once, then write a raw 12-bit value or a millivolt level:

#include "core.h"   // Core.ST.H5 only

core_dac_init();
core_dac_write(2048);       // mid-scale (raw 12-bit)
core_dac_write_mv(1650);    // 1.65 V

Cross-architecture support

Raw and millivolt reads are verified broadly; oversampling, continuous/scan, and DMA vary by Core, and the temperature sensor’s accuracy depends on whether the factory cal is bus-accessible. The DAC is H5-only:

See the implementation status for the full matrix.

API reference

ADC

int core_adc_read_pad(uint8_t pad);

int core_adc_read_mv_pad(uint8_t pad);

int core_adc_temp_decidegc(void);

int core_adc_vdd_mv(void);

hal_status_t core_adc_init(core_adc_t * adc, uint32_t resolution);

hal_status_t core_adc_add(core_adc_t * adc, uint8_t pad, uint32_t samp);

uint16_t core_adc_read(core_adc_t * adc, uint8_t pad);

uint32_t core_adc_read_mv(core_adc_t * adc, uint8_t pad);

int32_t core_adc_temp(core_adc_t * adc);

uint32_t core_adc_vdd(core_adc_t * adc);

hal_status_t core_adc_start_dma(core_adc_t * adc, uint16_t * buf, uint16_t len, hal_callback_t cb, void * ctx);

void core_adc_stop_dma(core_adc_t * adc);

uint16_t core_adc_dma_read(core_adc_t * adc, uint8_t pad);

DAC

void core_dac_init(void);

void core_dac_write(uint16_t val);

void core_dac_write_mv(uint16_t mv);

uint16_t core_dac_read(void);