UART in command mode conflict with GPIO pin

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Anonymous
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I made a project with UART to try high level APIs for command mode. UART clock is derived from VC3 for 1200bps. The code is from the UART's data sheet. Rx input is connected to P1.2 (HighZ) and Tx Output is connected to P1.4(Strong). Everything works fine. But when I change P1.6 mode from HighZ to StdCPU/Strong it stops working. The initial message is sent but it dosn't receive any more. The code has not been changed at all. Can somebody tell me what's wrong?

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ETRO_SSN583
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If you look at schematic there is a jumper that ties P1_6 to Rx of the translator chip.

   

 

   

Its JP1, so pull off that jumper, you should be good to go.

   

 

   

Regards, Dana.

   

 

   

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ETRO_SSN583
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If you do Read Modify Write operations on a given port, or it

   

has mixed I/O in it, you need to use shadow registers when working

   

with the port.

   

 

   

    

   

          

   

http://www.cypress.com/?rID=2900    AN2094

   

 

   

Regards, Dana.

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ETRO_SSN583
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You can always post your project for the forum to look at.

   

 

   

    

   

          

   

"File" 

   

“Archive Project”

   

 

   

Use Internet Explorer or Firefox to post, Chrome does not seem to work.

   

 

   

Regards, Dana.

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Anonymous
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Do you change P1.6 after the program started running. Or you change P1.6 in designer?

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Anonymous
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I change P1.6 in the designer. Not in code. Here is the project archived. It works ok. But when you change P1.6 Drive to Strong it stops. Tried to replace the PSoC chip with brand new. No success. Weird. 

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Anonymous
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My hardware is CY3210-PSoCEval1 kit.

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ETRO_SSN583
Level 9
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250 likes received 100 sign-ins 5 likes given

If you look at schematic there is a jumper that ties P1_6 to Rx of the translator chip.

   

 

   

Its JP1, so pull off that jumper, you should be good to go.

   

 

   

Regards, Dana.

   

 

   

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Anonymous
Not applicable

Thanks Dana! Problem solved.

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ETRO_SSN583
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Glad to assist.

   

 

   

I also learned, I use that board often, and had not realized those jumpers

   

were "dual" purposeing GPIO pins.

   

 

   

Regards, Dana.

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