TM4C1294NCPDT: SPI master mode 10MHz 8 bit data length issue

Briceag Cosmin

Intellectual 840 points

Part Number: TM4C1294NCPDT

Hello,

Trying to send data over SPI bus using SSI module 0. Although the frequency is correct I always see 0x00 on MOSI line.

The SPI is configured with 8 bit data length.

Any idea why this behavior ?

over 6 years ago

0 Bob Crosby over 6 years ago

TI__Guru 72500 points

Here are some ideas (hopefully some are trivial to discount).

1. You are sending 0x00 data

2. You did not configure the SSI0DATA0 and SSI0DATA1 pins properly

3. Your logic analyzer is on the wrong pins (SPIMO is pin 37, PA4; SPISI is pin 38, PA5; One pin is always TX the other RX. They do not change direction when changing from Master to Slave like on some devices.)

Here is a working sample project.

/cfs-file/__key/communityserver-discussions-components-files/908/7245.SPI_5F00_Master.zip

0 Briceag Cosmin over 6 years ago in reply to Bob Crosby

Intellectual 840 points

Hello Bob,

So, actually there was a HW issue. The wire was not bound correctly.

Thank you for you support !

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TM4C1294NCPDT: SPI master mode 10MHz 8 bit data length issue