Hi! I'm trying to make a simple counter, from 0 to 99 using 8 bits. In the GAL i have 2 inputs, one for the CLK and the other for the CLR. And 9 outputs, 4 for the units, 4 for the tens and 1 that just send '1' when the counter has reached the limit. I'm using Galaxy for the code. The code compiles well and i've also run a simulation and everything's fine. The outputs are sent to a bar of leds, and 7 leds are on all the time, nothing else happens. I'm using a G540 programmer. Here is the code: LIBRARY IEEE; USE IEEE.STD_LOGIC_1164.ALL; USE IEEE.STD_LOGIC_UNSIGNED.ALL; ENTITY CONTADOR IS PORT(CLK,CLR: IN STD_LOGIC; QUNI, QDEC: INOUT STD_LOGIC_VECTOR(3 DOWNTO 0); C: OUT STD_LOGIC ); ATTRIBUTE PIN_NUMBERS OF CONTADOR: ENTITY IS "CLK:1 CLR:2 C:23 " & "QDEC(3):22 QDEC(2):21 QDEC(1):20 QDEC(0):19 " & "QUNI(3):18 QUNI(2):17 QUNI(1):16 QUNI(0):15 "; END CONTADOR; ARCHITECTURE CUENTA OF CONTADOR IS BEGIN PROCESS(CLK,CLR) BEGIN IF(CLR='1') THEN QUNI <= "0000"; QDEC <= "0000"; C <= '0'; ELSIF(rising_edge(CLK)) THEN QUNI <= QUNI+1; C <= '0'; IF(QUNI="1001") THEN QUNI <= "0000"; QDEC <= QDEC+1; IF(QDEC="1010") THEN QUNI <= "0000"; QDEC <= "0000"; C <= '1'; END IF; END IF; END IF; END PROCESS; END CUENTA; HELP PLEASE!!!
> The code compiles well QUNI, QDEC: INOUT STD_LOGIC_VECTOR(3 DOWNTO 0); Why do you use inout ports? You just don't want to use local signals? You find it a nice trick to use inout ports, so you don't have to write that much code? As far as I see these ports are NOT bidirectional! This may cause problems. I recommend to use local signals for the counters and a assignment to the OUT ports for the LEDs. > and i've also run a simulation Thats ok... > and everything's fine. It it? So ... why do you have problems? Additionally to the INOUT ports obviously the problem is generating the correct programming file. Which GAL do you use?
Zuga Bachocos wrotes: The code compiles well and i've also run a simulation and everything's fine. The outputs are sent to a bar of leds, and 7 leds are on all the time, nothing else happens. So if the simulation succeeds you 've probably a bug in your hardware. Please check your layout and conections.
Thanks!I've changed the INOUT. The problem, i think, its when programming counters, because i tried to program other counter and it doesn't work. I thought it was the programmer but i've programmed succesfully a couple of 7-segment decoders and also a scanner for a keypad.The first bit of the units should be on and off at the same frcuency of the CLK, but with a led it stays on all the time but really low, and the other bits of the units and the tens do he same. I'm using GAL22V10.
> but with a led it stays on all the time but really low, You mean: the pin is low, so the led is on? > at the same frcuency of the CLK Whats the frequency? Where does the CLK come from? > The problem, i think, its when programming counters So you're able to generate some combinatorial logic, but not things with flipflops? Try the simplest counter: a one bit toggling flipflop...
1 | PROCESS(CLK) |
2 | BEGIN
|
3 | if rising_edge(CLK) then |
4 | toggle <= not toggle; |
5 | end if; |
6 | END PROCESS; |
7 | LED <= toggle; |
He have to read the Valu back here QDEC=QDEC+1. Ever when its on the right side of the Equation ! It's a long time since i programmed GALs but I think you have to define the MODE the GAL should have, so it can make use of the Flip Flops and you dont have to build them on your own with inout.
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