SPI MISO pin no connection

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Anonymous
Not applicable

I am using hc595 shift register and want to use SPI in transmit only mode, there is no MISO connection in hardware... if i left the MISO pin unconnected in creator it throws an error Terminal "miso" requires a connection when it is visible... How to deal with this, if I only want to transmit..

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Bob_Marlowe
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Easiest would be to use the SPIM in bi-directional mode. This will save you the MISO pin.

   

 

   

Bob

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

Easiest would be to use the SPIM in bi-directional mode. This will save you the MISO pin.

   

 

   

Bob

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Anonymous
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Thanks for immediate reply. In bidirectional mode I think I have to use a bidirectional pin as well, but my purpose is just using pin as output.

   

Other than that does SPI functions like send works in a similar manner or do I need to make some changes there ?

   

Isn't it possible to hook miso pin to logic high /low ?

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Bob_Marlowe
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I cannot see that the SPI bidirectional master macro uses a bi-directional pin. Check for yourself.

   

Isn't it possible to hook miso pin to logic high /low ? Probably not.

   

 

   

Bob

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Anonymous
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I will check and update here.

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Bob_Marlowe
Level 10
Level 10
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When in PSoC4 world, you may use the SCB based SPI interface which allows for removing MISO pin in configuration dialog.

   

 

   

Bob

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Anonymous
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You are right, but problem is hardware is already fabricated and I don't have this option because  for using SCB mode all pins for that SCB block should be free.

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