Hello. I connect the display on the st7789 driver to xiao ble nrf52840.
Unfortunately, the default is SPI with a maximum frequency of 8MHz and this is quite slow for display refresh.
I found out that the nrf52840 has one spi that operates at up to 32MHz. It’s called SPIM3. But I just can’t figure out how to turn it on.
To communicate with the display I use the TFT_espi library.
I am writing code in the Arduino environment.
Could you tell me how to enable this SPIM3 to get maximum speed with the display?
The SPI clock of XIAO nRF52840 is 8MHz when mbed is used for BSP, but can be set up to 32MHz when non mbed is used.
It depends on the library you are using, for example
tft.setSPISpeed(32000000UL);
You may also refer to the following link.
‘XIAO_nRF52840 mbed's SPI performance is only 1/3.5 of non-mbed's’