Using Digilent Nexys 2 board which has a rs232 port (uses the Spartan 3E
fpga).
Trying to test the rs232, i have a usb to rs232 cable and i use Putty
which all seems to be working ok. So i wrote this for the FPGA to loop
back RX and TX so the fpga would just echo back what ever data it got.
1 | library IEEE;
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2 | use IEEE.STD_LOGIC_1164.ALL;
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3 |
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4 | entity top is
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5 | Port ( rxd : in STD_LOGIC;
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6 | txd : out STD_LOGIC);
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7 | end top;
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8 |
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9 | architecture Behavioral of top is
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10 |
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11 | begin
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12 |
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13 | txd <= rxd;
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14 |
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15 | end Behavioral;
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Unfortunately once put on the fpga i can't write anything in the
terminal which i think is because the fpga is not echoing back the data.
Can anyone see the problem here? Or have a better way to test the rs232?
Thanks.