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Altera_Forum
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20 years ago

SPI Slave bug?

Has anybody used the SPI core as a slave device in a NIOS II implementation? If so, have you had relatively frequent data errors? There is no HAL for the SPI as slave, so I'm just using th...
Altera_Forum's avatar
Altera_Forum
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14 years ago

I believe I found the solution to this problem. I had my SPI slave running from a 40MHz source. The data rate I was using was <1MHz. I found that the lower data rate I would run my master at, the worse these errors became. I changed my SPI slave to run at a 1MHz rate. The errors went away. So it seems that your SPI slave clock should be close to the data rate you intend to run at. I'm not sure how close it has to be or what the upper limit on the SPI slaves data rate is.