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Altera_Forum
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11 years ago

Nios as slave with spi

Hello guys, I'm writing beacause I need some suggestions.. I have an FPGA running a NIOS2 processor. This processor will be interrogated by a master peripheral with the SPI protocol. I know tha...
Altera_Forum's avatar
Altera_Forum
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11 years ago

By the spi core docs (june 2011):

"..After a word is received by the slave, the master must de-asser the ss_n signal and reasserts the signal again when the next word is ready to be sent.."

So it seems that if you want to use the Altera's SPI interface you cannot transfer strings with variable byte length with the ssn low for all the time necessary to the transmission.