Reported from github: https://github.com/espressif/esp-idf/issues/1236
All the touch channels are enabled by default in hardware. This would interfere other RTC function on Touch IOs.
Disable touch function in touch_pad_init().
1. All the registers of touch sensor 8 and 9 are mismatched except the ‘dac’ field in touch register of RTC IO
2. To swap the index for sensor 8 and 9 in APIs.
append adc support and api
- esp_err_t adc2_config_width(adc_bits_width_t width_bit);
- esp_err_t adc2_config_channel_atten(adc2_channel_t channel, adc_atten_t atten);
- int adc2_get_voltage(adc2_channel_t channel);
1. Support built-in ADC for I2S.
2. Modify code of ADC, made no change to the original APIs.
3. Add APIs in I2S:
esp_err_t i2s_set_adc_mode(adc_unit_t adc_unit, adc1_channel_t adc_channel);
4. Add I2S ADC/DAC example code.
5. add old-fashion definition to make it more compatible
6. replase spi_flash_ APIs with esp_partition_ APIs
7. add example of generating audio table from wav
8. change example sound
Added component containg API that is able to correct raw ADC readings
into a voltage in mV. Also provided a helper function that combines
the process of getting the raw ADC1 reading then converting it to a
voltage in mV. In doing so, the adc1_get_voltage() function of the ADC
driver has been deprecated. Instead there is now adc1_get_raw to obtain
the raw ADC1 reading, and adc1_to_voltage() that gets the raw reading
and converts all in one function. Functions using the deprecated
adc1_get_voltage() have also been updated to use adc1_get_raw().
Conversion is based on ADC characteristics. The characteristics are based
on the ADC's v_ref, herefore the appropriate structure and functions have
been provided to obtain the ADC characteristics.
The existing ADC driver has also been modified by adding a function to
route the internal ADC reference voltage to a GPIO allowing users to measure
it manually.
Relevant documentation has also been updated
1. add sens_struct.h
2. add definition of RTCCNTL and RTCIO
3. modify touch pad examples
4. update example code.
5. add comments add option in menuconfig
6. fix issue that pad index 8 and 9 are mismatched
7. add touch_pad_read_filtered() api to get value filtered by iir filter
8. modify touch pad isr func
9. Make the items in perihperal.ld in the sequence of address
10. delete Kconfig for touch pad
11. add touchpad filter APIs to adjust the filter
12. add touch_pad into index.rst
13. add touch_pad in Doxyfile
14. add touch_pad.rst
The touch pad read function taks too much time within spin lock waiting for the "done bit". (about 7.6ms as we tested)
So we try to use a mutex on the touch read function and any other functions might change the "done bit".