SPI Communication

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Anonymous
Not applicable

Hi,

   

 

   

I posted my question in the other forum but got no answer.

   

The problem was I 'm trying to make 2 PSoC chip communicate via SPI.

   

PSoC5LP as master and  the PSoC4 as slave.

   

The problem is, MISO line (P0_2) of the PSoC5 seem to pull the pin low.

   

I have change the pin to P3_0 and everything works as expected.

   

Can anyone explained what happened?is P0_2 (Opamp ) input cannot be buffered?

   

Thank you.

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Bob_Marlowe
Level 10
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Probably you are working with some development kits. To help you more, will you please tell us exactly which?

   

The pins do not differ in their behaveour but on a Kit they could have some connections. Did you try to program your pin P0_2 and measure to see if it is ok?

   

 

   

Bob

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Anonymous
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 You are correct, i  am using CY8KIT-050.

   

According to the schematic pin P0_2 doesn't seem to be connected to any other hardware except to the header.

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Bob_Marlowe
Level 10
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Fine that you checked that, now you should try to check P0_2 for any damage.

   

 

   

Bob

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ETRO_SSN583
Level 9
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When you set up the pin what did you pick for initial state ? A "0" or a "1" ?

   

 

   

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ETRO_SSN583
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Image did not post, attached.

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Anonymous
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 The initial state is 0, as I mentioned before it seem like the pin is pull low.weird...

   

I test the pin as analog output and then as digital output , everything seem to be working.

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ETRO_SSN583
Level 9
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P2[0] is also tied to LCD data pin thru a 10K R, maybe thats what

   

you are seeing ?

   

 

   

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Anonymous
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 The pin is P0_2 not P2_0 

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HeLi_263931
Level 8
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Do you use any other component, lika the SAR ADC or OpAmps? P0[2] has some predefined functions, maybe they get used somewhere...

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Anonymous
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nope..just as SPI Master...and P0_2 as MISO line

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HeLi_263931
Level 8
Level 8
100 solutions authored 50 solutions authored 25 solutions authored

Strange. Can you use P0[2] as normal GPIO port (just assign a digital out pin to it which you toggle manually e.g. once per second, or maybe just as PWM output or so)?

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Anonymous
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Strange indeed ...I will test other functions (digital out/In).

   

Perhaps the pin was damaged somehow

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