Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Highlighted
Valued Contributor III
845 Views

uart code

What does the following code do? 

 

case(SW[3:0]) 

4'b0000: UART_TXD = RS422_1_TX; 

4'b0001: UART_TXD = RS422_2_TX; 

4'b0010: UART_TXD = RS422_3_TX; 

4'b0011: UART_TXD = RS422_3_TX; 

... 

verilog challenged:oops:
0 Kudos
4 Replies
Highlighted
Valued Contributor III
4 Views

Hi: 

This is an 16 to 1 multiplexer or mux. Based on the 4-bit selection term SW, the output is connected to the input where SW matches the case term 4'b0000, 4'b0001 etc. 

So if SW = 4'b0010, the output UART_TXD = input RS422_3_TX.
0 Kudos
Highlighted
Valued Contributor III
4 Views

Thank you very much!

0 Kudos
Highlighted
Valued Contributor III
4 Views

I am using an eval board. I am trying to communicate with a PC via the RS232.  

Can I just use the switches to send an 8 bit signal? It doesn't let me just assign the switches as an array to the UART TX?  

What am I doing wrong?  

Thanks,
0 Kudos
Highlighted
Valued Contributor III
4 Views

I'm trying to build a vhdl uart too. I think that the TX is only one bit long because it is a signal you have to modify according to your baudrate.

0 Kudos