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Altera_Forum's avatar
Altera_Forum
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14 years ago

SPI Problems

Hi, I'm trying to get handle with the SPI on a Nios II Core but I don't get it. I have a SPI master and a SPI Slave that I can try to transmit some data from the master to the slave. I connecte...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

Your ss signal is not asserted. Must be low when master is transmitting.

I see only now that you code is:

IOWR_ALTERA_AVALON_SPI_SLAVE_SEL(SPI_MASTER_BASE, SPI_SLAVE_BASE);

That's wrong. The correct one is:

IOWR_ALTERA_AVALON_SPI_SLAVE_SEL(SPI_MASTER_BASE, 1);