Mod 8 Counter AHDL Design w/ External Source

[lespaul5895]

I'm working on a project for my digital electronics class and part of it is designing a mod 8 counter using AHDL, I have the counter designed no problem but the only catch is the counter once it reaches the number 7 should stay there and not start over until an external source tells it to.

here's my code so far
SUBDESIGN mod8_counter
(
CLK, CLR :INPUT;
Y[2..0] :OUTPUT;
)

VARIABLE
count[2..0] :DFF;

BEGIN
count[].clk = clk;
IF !CLR THEN
count[] = count[] + 1;
END IF;
Y[] = count[];
END;

 

[berkeman]

IF !CLR THEN
count[] = count[] + 1;
END IF;

Seems like that's the part you need to modifiy the IF on, eh?

 

[lespaul5895]

I'm getting that my first if statement should be something to the effect of telling it that if y = 7 then it stays there else it will count up to 7 but I have no idea how to do that code, probably something easy but I'm still kinda new to this and I'm sure I'm just overlooking it.

 

[berkeman]

You're on the right track. Just do some more reading about IF statements and other conditional statements.

 

[lespaul5895]

SUBDESIGN mod8_counter
(
CLK, CLR :INPUT;
Y[2..0] :OUTPUT;
)

VARIABLE
count[2..0] :DFF;

BEGIN
count[].clk = clk;
IF !CLR THEN
IF count[] < 7 THEN
count[] = count[] + 1;
ELSE count[] = count[];
END IF;
END IF;
Y[] = count[];
END;

How's that look? I simulated and it seems to work ok?