On an RM44LS520, mibSPI1, I am seeing the BITERR flag set although the output data looks perfect on an oscilloscope.

Richard Derman2

The device has a 120 MHz clock, and a baud rate of 1 MHz.

In the scope shot below, the cyan trace is the enable line, the magenta trace is the clock, and the yellow trace is the data. I am outputting 0x7E.

The data look clean and show no jitter or anomalies. From this very typical trace I see no reason for the BITERR flag to be set.

My question is: has anyone reading this seen similar behavior, and if so, how was it rectified?

Thanks for any help that may be forthcoming.

over 8 years ago

0 Anthony F. Seely over 8 years ago

TI__Guru 68920 points

Rick,

I'm not sure this is related, but please confirm whether the package you are using is the 100 PZ or the 144 PGE .
Also which mode are you using the MibSPI in?

I need to check the datasheet & TRM for this device but what you report could be explained easily if the pinmux isn't configured correctly.
Just not sure if this device has that level of complexity on the SPI you are using.

0 Anthony F. Seely over 8 years ago in reply to Anthony F. Seely

TI__Guru 68920 points

Rick,

Ok so on this device the input mux isn't there for MibSPI1.

But I noticed MibSPI1 is a parallel SPI.

This *might* explain something. What value do you have in SPIPC0? I want to make sure it is 0x01010Exx or 0x01010Fxx.
Otherwise please make sure you only set the MibSPI1SIMO[0] and MibSPISOMI[0] for SPI mode. MibSPI1SIMO[1] and MibSPISOMI[1] need to be set for GPIO mode.

0 Richard Derman2 over 8 years ago in reply to Anthony F. Seely

Intellectual 260 points

Thanks. That fixed the problem.

0 Jun Xu over 8 years ago in reply to Anthony F. Seely

Prodigy 160 points

Hi Anthony,

Do you mean the peripheral can only be configured as traditional SPI device?

Thanks

Jun

0 Anthony F. Seely over 8 years ago in reply to Jun Xu

TI__Guru 68920 points

Jun,

I don't think I understand the question. I don't mean " configured as traditional SPI device?" although of course it has to be configured to match the usage in the application of the SPI pins.

-Anthony

Arm-based microcontrollers

Arm-based microcontrollers forum

On an RM44LS520, mibSPI1, I am seeing the BITERR flag set although the output data looks perfect on an oscilloscope.