S32k146 LPSPI0 doesn't work

[12914A]

Hi,

I tested the LPSPI example for S32k146, to add in future the communication with a sd-card via SPI. But it doesn't work. I use PTB0 - PTB3 (LPSPI0). While debugging, it stucks at the while loop in transmit / read function. I attach the functions (init, send, read).

Can anyone help?

Best regards

Sandra

[danielmartynek]

Hi @12914A,

Can you scope the bus?

Is the LPSPI0 sending something on the bus?

How do you call the write_byte() and read_byte() functions?

Regards,

Daniel

[12914A]

Hi Daniel,

thanks for your reply. 

The CS and CLK line work as expected. But on the MOSI line there is no data.

Here is how we call the write_byte() function:

for (b = 0 ; b < 0x0f; b++) //Send min 74+ clocks
{ write_byte(0xff);
}

but it stay stuck in the write_byte() in the following line:

while(((LPSPI0->SR & LPSPI_SR_TDF_MASK)>>LPSPI_SR_TDF_SHIFT)==0);

What could be the problem?

Best regards

Sandra

[danielmartynek · Accepted solution]

Hello Sandra,

How many of the 128 CLK cycles do you see at the pin?

If you don't read the RX data from the RX FIFO, set CFGR1[NOSTALL].

BR, Daniel