Part Number: AM3354
Hi，
Main chip： AM3354BZCZ100
SDK： RT 3.3
Hardware connection ：
The OLED screen (ssd1106) needs to be controlled by the SPI bus in the uboot phase.
How should the SPI program in the am3354 uboot phase be written?
For example, how to write data on the SPI bus, set the clock speed of the SPI and the mode of SPI ?
Can we make some suggestions or give some SPI operation routines for the am335x uboot phase ？
Hope for your help，Thank you.
BR
Hi Pavel,
Thanks for your advice, I now use the sspi command to control SPI peripherals.
Main chip： AM3354BZCZ100
SDK： RT 3.3
SPI1 pin configuration is as follows:
Hardware connection ：
As can be seen from the schematic diagram，the bus is 1 chip Select is 0.
In the uboot phase execute sspi 1: 0.3 32 A command, board error restart, as shown below:
uboot compiled as :
make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- am335x_boneblack_defconfig all
make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf-
Did not use the device tree. We use the MLO and u-boot.img to start the am3354 board.
Test the SPI0 bus command, as follows:
I need to control the peripherals on the SPI1 bus.
How can I solve the SPI1 error board restart problem ?
Hope to get your help, thanks.
BR
Hi Pavel,
When I execute the SSPI 1:0.0 32 A command, I add print to spi.c and omap3_spi.c, as shown in the following figure:
The spi_reset () function times is wrong when executing to the omap3_spi.c file, as shown in the following figure:
How should I solve this problem ?
How to use the SSPI command to control the peripherals on the SPI 1 bus ?
I hope you can help me, thank you.
BR
