Use of SPI_Status

Narendra Kulkarni29

Hello,

There is member element SPI_Status in the SPI_transaction strtuct. This is supposed to give the status of SPI Transfer. When I see the status after SPI _transfer is complete (both blocking and callback mode). I get random values, instead of the enum values of SPI_status. Where does it get updated? I have walked through the SPI Tiva driver and don't see this member element being updated. I am facing some SPI_transfer issues and am debugging the issue.

Please help me where this member element is getting updated

H/W and S/W details

TM4C129x Microcontroller

TI-RTOS 2.14

Tivaware 2.1.1.71b

CCS 6.1

TI-ARM Compiler 5.2.5

SPI device -> RFID reader from Maxim

Thanks in Advance

Narendrfa

over 9 years ago

0 Ashish Kapania over 9 years ago

TI__Mastermind 21645 points

Hi Narendra,

The TivaC SPI driver is missing the code to update the "status" field of the SPI_Transaction struct as you noted in your post. I filed a bug to track this issue (link below). Presently, only CC26xx SPI driver updates the "status" field.

If you are calling SPI_Transfer() in blocking mode, then the "status" field should not be required as the return value of SPI_Transfer() lets you know if the transaction completed or failed. In case of callback mode, if a failure happens due to bad arguments or a busy SPI bus, the SPI_Transfer() call will immediately return with a "false" bool value. If the SPI callback function is called, in all likelihood the transaction has succeeded so I don't think checking the "status" field will add much value.

Link to Bug (It may take several hours before the link is active):

https://cqweb.ext.ti.com/cqweb/main?command=GenerateMainFrame&service=CQ&schema=SDO-Web&contextid=SDOWP&entityID=SDOCM00119283&entityDefName=IncidentReport&username=readonly&password=readonly

Best,
Ashish

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Use of SPI_Status