alex/esp-idf
alex/esp-idf
1
0
Fork 0
mirror of https://github.com/espressif/esp-idf.git synced 2024-10-05 20:47:46 -04:00
Code Issues Actions 2 Packages Projects Releases Wiki Activity

adc: no longer support adc2 continuous mode on esp32c3

Browse Source 
Due to HW limitation, we don't support this anymore. On c3, ADC2 under continuous  mode is not stable.

However, you can enable CONFIG_ADC_CONTINUOUS_FORCE_USE_ADC2_ON_C3_S3 to force use
ADC2.

Refer to errata to know more details:
https://www.espressif.com/sites/default/files/documentation/esp32-c3_errata_en.pdf
This commit is contained in:
Armando 2022-12-16 12:47:14 +08:00 committed by BOT
parent dc4c9c087f
commit 9b4986dd2c
4 changed files with 33 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
components/driver/Kconfig
View File

@ -19,6 +19,17 @@ menu "Driver configurations"
For testing, disable this option so that we can measure the output of DAC by internal ADC.
config ADC_CONTINUOUS_FORCE_USE_ADC2_ON_C3_S3
depends on IDF_TARGET_ESP32C3
bool "Force use ADC2 continumous mode on ESP32C3"
default n
help
On ESP32C3, ADC2 Digital Controller is not stable. Therefore,
ADC2 continuous mode is not suggested on ESP32C3
If you stick to this, you can enable this option to force use ADC2 under above conditions.
For more details, you can search for errata on espressif website.
endmenu # ADC Configuration
menu "SPI configuration"

15
components/driver/esp32c3/adc.c
View File

@ -576,6 +576,21 @@ esp_err_t adc_digi_controller_config(const adc_digi_config_t *config)
}
ADC_CHECK(config->sample_freq_hz <= SOC_ADC_SAMPLE_FREQ_THRES_HIGH && config->sample_freq_hz >= SOC_ADC_SAMPLE_FREQ_THRES_LOW, "ADC sampling frequency out of range", ESP_ERR_INVALID_ARG);
#if !CONFIG_ADC_CONTINUOUS_FORCE_USE_ADC2_ON_C3_S3
for (int i = 0; i < config->adc_pattern_len; i++) {
if (config->adc_pattern[i].unit == ADC_NUM_2) {
//we add this error log to hint users what happened
ESP_LOGE(ADC_TAG, "ADC2 continuous mode is no longer supported, please use ADC1. Search for errata on espressif website for more details. You can enable CONFIG_ADC_CONTINUOUS_FORCE_USE_ADC2_ON_C3_S3 to force use ADC2");
/**
* On all continuous mode supported chips, we will always check the unit to see if it's a continuous mode supported unit.
* However, on ESP32C3 and ESP32S3, we will jump this check, if `CONFIG_ADC_CONTINUOUS_FORCE_USE_ADC2_ON_C3_S3` is enabled.
*/
ESP_LOGE(ADC_TAG, "Only support using ADC1 DMA mode");
return ESP_ERR_INVALID_ARG;
}
}
#endif //#if !CONFIG_ADC_CONTINUOUS_FORCE_USE_ADC2_ON_C3_S3
s_adc_digi_ctx->digi_controller_config.conv_limit_en = config->conv_limit_en;
s_adc_digi_ctx->digi_controller_config.conv_limit_num = config->conv_limit_num;
s_adc_digi_ctx->digi_controller_config.adc_pattern_len = config->adc_pattern_len;

5
docs/en/api-reference/peripherals/adc.rst
View File

@ -58,8 +58,9 @@ ADC Limitations
.. only:: esp32c3
- A specific ADC module can only work under one operating mode at any one time, either Continuous Read Mode or Single Read Mode.
- ADC1 and ADC2 can not work under Singel Read Mode simultaneously. One of them will get blocked until another one finishes.
- For continuous (DMA) read mode, the ADC sampling frequency (the ``sample_freq_hz`` member of :cpp:type:`adc_digi_config_t`) should be within ``SOC_ADC_SAMPLE_FREQ_THRES_LOW`` and ``SOC_ADC_SAMPLE_FREQ_THRES_HIGH``.
- For continuous (DMA) read mode, the ADC sampling frequency (the ``sample_freq_hz`` member of :cpp:type:`adc_digi_config_t`) should be within ``SOC_ADC_SAMPLE_FREQ_THRES_LOW`` and ``SOC_ADC_SAMPLE_FREQ_THRES_HIGH``
- ADC2 continuous (DMA) mode is no longer supported, due to hardware limitation. The results are not stable. This issue can be found in `ESP32C3 Errata <https://www.espressif.com/sites/default/files/documentation/esp32-c3_errata_en.pdf>`. For compatibility, you can enable :ref:`CONFIG_ADC_CONTINUOUS_FORCE_USE_ADC2_ON_C3_S3` to force use ADC2.
Driver Usage
------------

9
examples/peripherals/adc/esp32c3/adc/main/adc_dma_example_main.c
View File

@ -8,7 +8,7 @@
#define TIMES 256
static void continuous_adc_init(uint16_t adc1_chan_mask, uint16_t adc2_chan_mask, adc_channel_t *channel, uint8_t channel_num)
static void continuous_adc_init(uint16_t adc1_chan_mask, adc_channel_t *channel, uint8_t channel_num)
{
esp_err_t ret = ESP_OK;
assert(ret == ESP_OK);
@ -17,7 +17,7 @@ static void continuous_adc_init(uint16_t adc1_chan_mask, uint16_t adc2_chan_mask
.max_store_buf_size = 1024,
.conv_num_each_intr = 256,
.adc1_chan_mask = adc1_chan_mask,
.adc2_chan_mask = adc2_chan_mask,
.adc2_chan_mask = 0,
};
ret = adc_digi_initialize(&adc_dma_config);
assert(ret == ESP_OK);
@ -61,10 +61,9 @@ static void continuous_read(void *arg)
memset(result, 0xcc, TIMES);
uint16_t adc1_chan_mask = BIT(0) | BIT(1);
uint16_t adc2_chan_mask = BIT(0);
adc_channel_t channel[3] = {ADC1_CHANNEL_0, ADC1_CHANNEL_1, (ADC2_CHANNEL_0 | 1 << 3)};
adc_channel_t channel[3] = {ADC1_CHANNEL_0, ADC1_CHANNEL_1};
continuous_adc_init(adc1_chan_mask, adc2_chan_mask, channel, sizeof(channel) / sizeof(adc_channel_t));
continuous_adc_init(adc1_chan_mask, channel, sizeof(channel) / sizeof(adc_channel_t));
adc_digi_start();
int n = 20;