* SPI: Fix discarded-qalifiers warning when compiling with all warnings
This fixes an error introduced with changeset b847f41 which
tightened the use of const for read-only data. The helper
funtion __transferBytes also requires the const qualifier on
outgoing data. Without this change a warning is displayed
when compiling with the Arduino IDE set to display "All"
compiler warnings.
Tests:
- Build an ESP32 SPI sketch that uses static const data to send
to an SPI device using the SPI.transferBytes() API
* SPI:Ensure all local functions are marked static
This audits all functions in the esp32-hal-xpi.c module and
ensures that any functions entirely local to the module are
marked as static.
Tests:
- Build with Arduino set to show all warnings and ensure none
are displayed
* SPI: Remove unused local __spiTranslate24 function
This removes the __spiTranslate24() function which is unused.
This changes all SPI functions that take data pointers which are
not modified so that the declaration is const. This allows them
to be used with const data (i.e. held in flash). No functional
changes are required.
The defnitions of spiWrite() and spiTransferBytes() in
esp-hal-spi.h/c have been updated to be consistent.
Tests:
- Build a simple sketch using SPI.writePattern() and
SPI.transferBytes() which uses const data and verify that the
attached device functions as expected.
* Add APB change callbacks and move cpu code to own file
* Properly set esp_timer and FreeRTOS tick dividers
* Improve updated devisors
* No need to update REF_TICK yet
* Add initial handling for UART baud change
* fix uartWriteBuf and uartDetectBaudrate
* trigger callbacks even when APB did not change
* toggle UART ISR on CPU change
* add XTAL freq getter and add cpu freq validation
* Support CPU frequency changes in I2C (#2287)
**esp32-hal-i2c.c**
* add callback for cpu frequency changes
* adjust fifo thresholds based on cpu frequency and i2c bus frequency
* reduce i2c bus frequency if differential is too small
**Wire.h**
* version to 1.1.0
* Implement clock change for the other peripherals
* remove bad CPU clock values from the menu
* Add note to CPU freqs that support WiFi and BT
* Add support to HAL for APB frequencies different than 80MHz
* Add support for CPU frequencies in the IDE board menu
* Switch to fast set_config
* Add method to uart so debug can be reassigned after apb frequency switch
* Return real APB frequency
It appears that the configurations for `ck_out_edge` were inverted for `SPI_MODE2` and `SPI_MODE3`. You can check the technical reference manual on page 76, table 23 "Clock Polarity and Phase, and Corresponding SPI Register Values for SPI Master".
I've check with my oscilloscope that the current configuration is wrong and this fix corrects the issue.
IDF Options:
- Autostart Arduino (implements app_main)
- Disable HAL locks
- Set HAL debug level
- Auto-connect STA if configured (else will connect after WiFi.begin())
