Issue with spi reading on the STM32-nucleo-F767ZI

[Photona]

Hello,

I am trying to implement spi writing/reading to the slave device using STM32 microcontroller.
I have spi datagram define here on the page 25 that also define slave manufacture vendorID at address 0x0200.

Using below code, I tried to read vendorID and get bytearray([b'x00\x00\x00\x00']) :

import machine

cs = machine.Pin('SPI3_NSS', machine.Pin.OUT)
sck =machine.Pin('SPI3_SCK', machine.Pin.OUT)
mosi =machine.Pin('SPI3_MOSI', machine.Pin.OUT)
miso =machine.Pin('SPI3_MISO', machine.Pin.OUT)

spi = machine.SPI(3, baudrate=1000000, polarity=0, phase=0)

data_in = bytes(bytearray( [0x04, 0x01, 0x00, 0x00] ) ) #register 0x0200 of the slave
data_out =  bytearray(4)

cs.off()
spi.write_readinto(data_in, data_out)
cs.on()

Thank you for help.

 

[KlausST]

Hi,

No error description, no question... no schematic

What do you expect us to do?

Klaus

 

[Photona]

Hello Klaus,

Thank you for your reply.

I do not have errors in micropython.

But responce from SPI is b'\x00\x00\x00\x00' and I expect to get reading from the specified register (0x0200) 0xE0CF.

I want to have confirmation that micropython code that I use is correct and I use correct phase and polarity.

What information do you need? I am happy to provide more info.