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Altera_Forum
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8 years ago

Trying to implement SPI slave in Cyclone IV - why this isn't working?

Hi, i'm trying to implement some practical stuff in Cyclone IV. For a start i need SPI slave which will write data received from master to dual port RAM. I'm struggling with basics in SPI receiver co...
Altera_Forum's avatar
Altera_Forum
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8 years ago

Is the code you've posted the source for this or the schematic? The schematic is missing the inverter in the Q -> D feedback path - something you have included in your code.

In the code you've not explicitly declared that the output signal 'miso' is a register. Try changing that to:
  output reg miso,
If the schematic is what Quartus has interpreted your code to be then I think we have the answer - no inverter.

If the schematic is your source, add the inverter.

Cheers,

Alex