This commit removes the lookup table mode due to inferior performance when compared
to linear mode under attenuation 0, 1 and 2. However small portions of the lookup table
are kept for the higher voltages of atten 3 (above ADC reading 2880). That voltage range
in atten 3 has non linear characteristics making the LUT performan better than linear mode.
This commit updates the esp_adc_cal ocmponent to support new calibration methods
which utilize calibratoin values stored in eFuse. This commit includes LUT mode
requirement from github(https://github.com/espressif/esp-idf/issues/805): to provide the position in the buffer of the pattern detected.
requirement from AT application: in AT app, when no hardware flow control is enabled, in some situation the rx buffer might be full, and the terminator “+++” might be lost, we can use pattern detect interrupt to avoid missing the terminator. When pattern detect interrupt happens, it will not send a data event at the same time.
1. Add API to get position of detected pattern in rx buffer
2. Modify UART event example
3. Add comments for uart_flush, add alias API uart_flush_input to clear the rx buffer
4. Modify the way rx_buffered_len is calculated
Reported from different sources from github or bbs:
https://github.com/espressif/esp-idf/issues/680https://github.com/espressif/esp-idf/issues/922
We tested reading several sensor or other I2C slave devices, if the power and SDA/SCL wires are in proper condition, everything works find with reading the slave.
If we remove the power supply for the slave during I2C is reading, or directly connect SDA or SCL to ground, this would cause the I2C FSM get stuck in wrong state, all we can do is the reset the I2C hardware in this case.
After this commit, no matter whether the power supply of I2C slave is removed or SDA / SCL are shorted to ground, the driver can recover from wrong state.
We are not sure whether this the save issue with the reported one yet, but to make the driver more robust.
Further information:
1. For I2C master mode, we have tested different situations, e.g., to short the SDA/SCL directly to GND/VCC, to short the SDA to SCL, to un-plug the slave device, to power off the slave device. Under all of those situations, this version of driver can recover and keep working.
2. Some slave device will die by accident and keep the SDA in low level, in this case, master should send several clock to make the slave release the bus.
3. Slave mode of ESP32 might also get in wrong state that held the SDA low, in this case, master device could send a stop signal to make esp32 slave release the bus.
Modifications:
1. Disable I2C_MASTER_TRAN_COMP interrupt to void extra interrupt.
2. Disable un-used timeout interrupt for slave.
3. Add bus reset if error detected for master mode.
4. Add bus clear if SDA level is low when error detected.
5. Modify the argument type of i2c_set_pin.
6. add API to set timeout value
7. add parameter check for timing APIs
using apll_param to setup APLL
new apll calculation method, much faster
validate freq calculation
Ensure that the i2s frequency is greater than the hardware limit
Add description of how to calculate apll clock, support apll for other 16-bits audio, check rev0 chip
correct space
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
Jiang Jiang Jian