Using RX to Print a Character on the LCD Display

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Anonymous
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 I am trying to print a recieved character to the LCD display but everytime I run the program I just end up getting random characters. I know that this could have something to do with the baud rates being off but I know for a fact that the sender is sending at a baud rate of 19200 and that is what I am trying to recieve at. Can someone please take a look at what I have and let me know if you see anything wrong? Thanks!

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Bob_Marlowe
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Check first your LCD-connection to verify that it works as required.

   

I cannot find a bug in your program, so check the baud-rate and the voltage-level at your Rx input with a crt or a logic analyzer.

   

Your PSoC1 is set to 5V internally, is that the level of your incoming signal?

   

 

   

Bob

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Anonymous
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 The incoming signal is actually 3.3 volts. Could that be the cause for the random characters?

   

EDIT: I actually just changed the global resources power setting to 3.3V and it still isn't displaying the correct data.

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Bob_Marlowe
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Yes, of course. Problem can be that your LCD may not run at 3.3V, or will it work at that voltage? If so, set the power for the PSoC on board to 3.3V and in the chip view to 3.3/24MHz.

   

 

   

Bob

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Anonymous
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 I changed the setting to 3.3V/24MHz but I can't find the other setting.

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Bob_Marlowe
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You are probably using a PSoC1 development kit that can be jumpered to 3.3V, have a look into the docs

   

 

   

Bob

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Bob_Marlowe
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Too bad: I just checked the docs for the CY8CKit 3210. It says that the LCD will not work at 3.3V, but you will need that for interfacing your Rx input.

   

 

   

Bob

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ETRO_SSN583
Level 9
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You could try placing in all LCD input lines a 1K R, or

   

any bidirectional line same, and running LCD on 3.3.

   

LCD output lines leave out R.

   

 

   

That could get you up and running and protect LCD from damage due

   

to excessive drive over its Vdd rail, and still meet Vih for the PSOC from

   

LCD output lines.

   

 

   

Give it a try.

   

 

   

Regards, Dana.

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