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Altera_Forum's avatar
Altera_Forum
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16 years ago

Bidirectional SPI switch?

This is a complex problem which I am very unsure of, the basic idea is that I want code that switches between 3 SPIs. I was startled when I noticed the statement that I was about to write ...
Altera_Forum's avatar
Altera_Forum
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16 years ago

In my opinion, the problem is a lack of clarity about the required prerequisites of a bidirectional "switch". A FPGA doesn't offer bidirectional bus switches of analog switch type. It can implement bidirectional buffers, similar e.g. to a 74HC245, that however need a control signal to decide about the actual data direction.

You have to find out, how this direction information can be deterrmined.