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Unable to read Pmod GPS UART data - Nexys 3


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Greetings,
It is my first time here so I apologise for my mistakes,
I started a new project where I am using Nexys 3 board with a Pmod GPS module.
I found a UART receiver/transmitter on the internet I wanted to test it out. So I connected the receiver to the USB UART Rx pin, in order to send from Serial COM data and then transmit back to the Serial COM the data I have sent. When I am sending a character from the serial, I receive the same character from the UART transmitter so I think that both of the components work fine. When I am sending the character A, I receive back the character A. My next step is to connect to the receiver the Rx pin of the GPS to read NMEA Sentences. In the manual it says that the GPS works at 9600 baud rate so I tune the code for 9600 baud rate. I start reading the NMEA but the serial out is garbages(I will post a photo for the results).
In the top.v module a connect the two modules like this:

receiver R1(clk, reset, RxD, data); // RxD is the serial output from GPS and data is the 8 bit output from UART
// transmitter receives the 8 bit data from the above module
transmitter T1(clk, reset, transmit, data, TxD); // data is the input and we send the serialized data back to the Tera Term serial COM

Is there any mistake with the connection?
Is there a problem with the baud rate? Because I have tested all the baud rates available but I had no result.

 

This is the result with 115200 baud rate
115200_baud.png.0460ae11474b5899518f7d9ce9ae7191.png

And these are the results for 9600 baud

9600_baud.png.ac7ba8fca4ae739ac3c98a01fb457c37.png

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Hello,
Can you post the source of your UART implementation?
Also, does your implementation use any parity bits? In my case, using a parity bit made the terminal also display garbage.

Best wishes,
Eduard
 

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