---
name: ADC And DAC Bare Metal
slug: adc-and-dac-bare-metal
category: DevOps
description: ADC And DAC Bare Metal configures ADC sampling, calibration, DMA circular buffers, and DAC output on microcontrollers. Use it for reading analog sensors, continuous sampling, or generating analog voltages.
github: "https://github.com/mohitmishra786/low-level-dev-skills/tree/main/skills/baremetal/adc-dac-baremetal"
language: JavaScript
stars: 194
forks: 27
install: "npx degit https://github.com/mohitmishra786/low-level-dev-skills/tree/main/skills/baremetal/adc-dac-baremetal ~/.claude/skills/adc-dac-baremetal"
installs_to: ~/.claude/skills/adc-dac-baremetal
source_path: skills/baremetal/adc-dac-baremetal/SKILL.md
collection_size: 25
category_size: 973
collection_url: "https://dirskills.com/collections/mohitmishra786/low-level-dev-skills"
added: 2026-09-05T05:31:25.579Z
last_synced: 2026-09-05T05:31:25.579Z
canonical_url: "https://dirskills.com/skills/adc-and-dac-bare-metal"
---

# ADC And DAC Bare Metal

ADC And DAC Bare Metal configures ADC sampling, calibration, DMA circular buffers, and DAC output on microcontrollers. Use it for reading analog sensors, continuous sampling, or generating analog voltages.

**Install:**

```bash
npx degit https://github.com/mohitmishra786/low-level-dev-skills/tree/main/skills/baremetal/adc-dac-baremetal ~/.claude/skills/adc-dac-baremetal
```

## README

# ADC and DAC (Bare-Metal)

## Purpose

Configure ADC and DAC peripherals: channel selection, sampling times, calibration sequences, DMA circular buffers, and DAC static/dynamic output.

## When to Use

- Reading analog sensors (temperature, voltage)
- Audio or control voltage output via DAC
- Continuous sampling with DMA
- Post-reset ADC calibration on STM32

## Workflow

### 1. STM32 ADC single conversion

```c
/* Enable ADC1 and GPIOA clock; PA0 analog mode */
ADC1->CR2 |= ADC_CR2_ADON;
for (volatile int i = 0; i < 10000; i++);  /* stabilization — RM value */

ADC1->SMPR2 |= ADC_SMPR2_SMP0_2;  /* 84 cycles sample time ch0 */
ADC1->SQR3   = 0;                 /* channel 0, 1 conversion */
ADC1->CR2   |= ADC_CR2_SWSTART;

while (!(ADC1->SR & ADC_SR_EOC))
    ;
uint16_t sample = ADC1->DR;
```

Run `ADC_Calibration()` / `ADC_CR2_RSTCAL/CAL` per RM on F1/F4 families.

### 2. DMA circular ADC

```c
/* ADC1 → DMA2 Stream0, circular mode into buffer[64] */
/* Configure DMA: periph-to-mem, halfword, increment mem, circular */
ADC1->CR2 |= ADC_CR2_DMA | ADC_CR2_CONT;
DMA2_Stream0->CR |= DMA_SxCR_EN;
```

Half-transfer / transfer-complete IRQs for double buffering.

### 3. DAC output (STM32)

```c
RCC->APB1ENR |= RCC_APB1ENR_DACEN;
DAC->CR |= DAC_CR_EN1;
DAC->DHR12R1 = 2048;  /* mid-scale 3.3V reference */
```

### 4. Agent usage

```
/adc-dac-baremetal Set up ADC1 channel 0 with DMA circular buffer
```

## Common Problems

| Symptom | Cause | Fix |
|---------|-------|-----|
| Noisy readings | Short sample time | Increase SMP bits |
| Stuck EOC | Clock not enabled | RCC ADC enable |
| Wrong voltage | Vref not 3.3V | Measure VDDA; calibrate |
| DMA corrupt | Buffer alignment | Use `uint16_t` aligned buffer |

## Related Skills

- `skills/baremetal/dma-baremetal` — ADC DMA streams
- `skills/baremetal/timers-pwm-baremetal` — ADC external trigger
- `skills/baremetal/gpio-baremetal` — analog pin mode