[Lancelot] 1st post!

Tommy Thorn tommy at numba-tu.com
Thu Jan 29 17:17:50 PST 2004

> I think there is actually an output pin to "load safe"; you can also
> write a config from the EP1C20 so...

Yes, it makes perfect sense in retrospect, but it was puzzling at first.

>> 1) Missing an "else" in an
>>      if (...) begin ...
>>      end else if (....) begin
> Same happens under C :)

:-) I can't explain why, but I've never made that mistake under C.

>> 2) Asynchronous latches, like
>>    always @*
>>      if (foo) bar <= 1;
>>    are prone to glitches (did _not_ show up under Icarus).
> Yeah, I think it's a good methodology to only use clock-driven elements.

Amen!  And it's not like I didn't know, but this is a typical instance of
"throw-away" code/logic written for debugging.  It wasn't intended to be a
latch, but obviously there were missing cases and voila! .. a glitch
catching latch was produced.  I guess the higher-order lesson here has to
do with throw-away code ... :-)

> Where can one get Icarus?  Sounds really interesting...

Google: http://www.icarus.com/eda/verilog

The released version is a bit old, so I always grab the lastest snapshot.

Now for something else: does anyone on this list (heh) know of a way to
get Quartus to launch programming automatically upon completing the
compile?  I'm really annoyed with the "select the .cdf windows and hit the
program button" cycle.

To the people out there that thinks we don't need faster computers: try


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