Hi all,
I'm using the latest version of the lib from: https://raspberry-projects.com/pi/progr ... e-mccauley
The CM4 Lite is on a rPi "Compute Module 4 IO Board".
I've written a very simple C util to communicate with my device (spi slave).
Watching MISO/MOSI/CK/CS on a DSO, everything looks fine. Data is sent to my device on MOSI, and the device sends data back on MISO.
The problem is data_in[] is always full of 0xFF.
I've tried directly connecting MISO to GND, but that make no difference.
Has anyone come across this?
Thanks.
I'm using the latest version of the lib from: https://raspberry-projects.com/pi/progr ... e-mccauley
The CM4 Lite is on a rPi "Compute Module 4 IO Board".
I've written a very simple C util to communicate with my device (spi slave).
Watching MISO/MOSI/CK/CS on a DSO, everything looks fine. Data is sent to my device on MOSI, and the device sends data back on MISO.
Code:
bcm2835_init();bcm2835_spi_begin();bcm2835_spi_setChipSelectPolarity(BCM2835_SPI_CS0, 0);bcm2835_spi_setClockDivider(BCM2835_SPI_CLOCK_DIVIDER_512);bcm2835_spi_setDataMode(BCM2835_SPI_MODE0);bcm2835_spi_chipSelect(BCM2835_SPI_CS0);...uint8_t data_out[16] = "hello world 1234";uint8_t data_in[16] = {0};bcm2835_spi_transfernb((char*)data_out, (char*)data_in, sizeof(data_out));I've tried directly connecting MISO to GND, but that make no difference.
Has anyone come across this?
Thanks.
Statistics: Posted by MWP — Thu Feb 08, 2024 8:26 am