S32KのトピックS32K146 LPSPI transfer bytes

S32K146 LPSPI transfer bytes

lc12138 — Sat, 02 Apr 2022 02:46:31 GMT

Hi,

I try to transfer and receive 28-bytes data with s32k146.And I used the code as follow:

LPSPI_DRV_MasterTransfer(INST_LPSPI_2, masterDataSend, masterDataReceive, BUFFER_SIZE);
flag = ( LPSPI_DRV_MasterGetTransferStatus(INST_LPSPI_2, bytesRemained) == STATUS_SUCCESS);

masterDataSend is data which I want to send and masterDataReceive is which I want to receive,BUFFER_SIZE is set to 28u.

However, while flag is true the bytesRemained is 0,and Receive buff is all 1.

Is anything in my conde wrong?And how could I find problem.

Thanks

Re: S32K146 LPSPI transfer bytes

danielmartynek — Mon, 04 Apr 2022 08:12:44 GMT

Hi,

The source code in that .rar file is not readable.

Can you attach it again?

Regarding the code that you posted here,

flag = ( LPSPI_DRV_MasterGetTransferStatus(INST_LPSPI_2, bytesRemained) == STATUS_SUCCESS);

The function will not return STATUS_SUCCESS immediately.

Can you use something like this intead?

LPSPI_DRV_MasterTransfer(INST_LPSPI_2, masterDataSend, masterDataReceive, BUFFER_SIZE); while(LPSPI_DRV_MasterGetTransferStatus(INST_LPSPI_2, bytesRemained) != STATUS_SUCCESS);

If you want to receive all the data transmitted by the master, connect MOSI to MISO in a loop.

Have you scoped the SPI bus with a logic analyzer?

BR, Daniel

Re: S32K146 LPSPI transfer bytes

lc12138 — Thu, 07 Apr 2022 01:25:18 GMT

Thanks,

I tried to use

while(LPSPI_DRV_MasterGetTransferStatus(INST_LPSPI_2, bytesRemained) != STATUS_SUCCESS);

but bytesRemained is still 0.

I sent a 9-bytes 0x55 to a LTC6820, and I used a oscilloscope to scope the SPI bus in 6820 sideMOSI(4bytes)MISO(4bytes)MISO(9bytes)

you could see that MOSI signal is actually 0x55, but MISO signal is not good, although its also 9 bytes.

Re: S32K146 LPSPI transfer bytes

danielmartynek — Thu, 07 Apr 2022 07:20:52 GMT

Hi @lc12138,

Can you disconnect the LTC6820 and connect MOSI - MISO instead?

Just to test the code.

BR, Daniel