Fix spiTransaction not updating clock line immediately (#9221) #9333
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Description of Change
This PR fixes #9221 by forcing SPI clock line to update within
spiTransaction
.This is especially important when sharing a single SPI bus between devices with different SPI modes.
Notable use case is using SD card (SPI mode 0) and ST7789-based TFT display (mode 3).
Tests scenarios
Tested with ESP32-C3 SuperMini board.
Related links
SPI.beginTransaction
does not set SCK value until the first write #9221Arduino_ESP32SPI
:startWrite
sets CPOL/CPHA too late moononournation/Arduino_GFX#433