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PSoC™ 5, 3 & 1 Forum Discussions

KrDe_284951
Level 4
Level 4
10 replies posted 10 questions asked 5 replies posted

I'm using the emfile component to address an SD card in combination with other hardware devices having an SPI hardware. I don't have enough pins to use 2 SPI interfaces (one  for the SD card and one for the other SPI devices). Can these 2 be multiplexed in one or other way?

Thanks for your suggestions

Kris

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1 Solution

The connection is external to the PSoC. SPI is a bus interface which is able to drive several slaves. The slave to communicate with is selected by the select line "ss". The SPI component allows for multiple ss lines, but you may use your own signal to drive an ss_1 pin. Keep in mind, ss is active low.

Bob

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Bob_Marlowe
Level 10
Level 10
First like given 50 questions asked 10 questions asked

You just need one more pin for the ss line. All other signals (mosi, miso, clk) can be shared.

Bob

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In my design file I have an SPI master with its miso, mosi, sclk pins and in the emfile component I have comparable pins. How do I link those pins in the cydwr to be the same hardware pins?

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The connection is external to the PSoC. SPI is a bus interface which is able to drive several slaves. The slave to communicate with is selected by the select line "ss". The SPI component allows for multiple ss lines, but you may use your own signal to drive an ss_1 pin. Keep in mind, ss is active low.

Bob

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I think the solution is to use the SPI functions defined in emFile.c in stead of defining another SPI component in the design file and write a wrapper to access my other devices.

Thanks for your advice