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Altera_Forum
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20 years ago

SPI PUZZLE

Hello, all I have problems with SPI as follows. As you know, SPI is a 3 wire interface and a SPI should have 3 signals commonly, but in SOPC Builder, a SPI have 4 signals actully. They a...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
20 years ago

Hi,

> Then, how should I connect them?

Because SPI core data in/out port are mono-direction, but slave-device data port is bi-direction. So, you should add a tri-buffer to connect between device and master. ss_n is the output-en for tri-buffer.

LiangYi