W
whygee
Guest
Hello group,
These days i'm back at A3P hacking and i fight against the
tools and the elements, and probably against something i don't
even know, so i'm asking the wise and experimented among you...
Basically, a simple FIFO block (like 8b * 512) works.
well, i use it just as a fast-to-slow circuit interface
and i don't expect FULL status by design.
I can even take advantage of word size conversion, i tried
16->8 (dropping the MSB) with some success.
But when i want to do smaller sizes, like 16->1, it... doesn't work.
output remains low, no sign of serialised signal.
i see nothing about that in the datasheet and handbook.
so where to turn when "it doesn't work" ?
(except this group)
ok so let's imagine i can still work with 8b->8b.
i use the "EMPTY" flag to indicate that there is something
available on the output. well, i don't know why but i see
nothing on this signal :-/ it is normally registered on
the (slow) read clock but i see nothing normal.
Let's be clear : i don't do any high-speed stuff or crazy
frequency domain crossing. it's in the 100KHz to 25MHz range,
and I can look at the outputs with my faithful analog T'475.
no problem with catching a 40ns pulse.
So if anyone has any information about Actel ProASIC3's FIFO,
concerning the extreme size conversions (16in, 1out) or/and
the Empty flag, please step up ! If one of them is solved,
i'm saved
yg
--
http://ygdes.com / http://yasep.org
These days i'm back at A3P hacking and i fight against the
tools and the elements, and probably against something i don't
even know, so i'm asking the wise and experimented among you...
Basically, a simple FIFO block (like 8b * 512) works.
well, i use it just as a fast-to-slow circuit interface
and i don't expect FULL status by design.
I can even take advantage of word size conversion, i tried
16->8 (dropping the MSB) with some success.
But when i want to do smaller sizes, like 16->1, it... doesn't work.
output remains low, no sign of serialised signal.
i see nothing about that in the datasheet and handbook.
so where to turn when "it doesn't work" ?
(except this group)
ok so let's imagine i can still work with 8b->8b.
i use the "EMPTY" flag to indicate that there is something
available on the output. well, i don't know why but i see
nothing on this signal :-/ it is normally registered on
the (slow) read clock but i see nothing normal.
Let's be clear : i don't do any high-speed stuff or crazy
frequency domain crossing. it's in the 100KHz to 25MHz range,
and I can look at the outputs with my faithful analog T'475.
no problem with catching a 40ns pulse.
So if anyone has any information about Actel ProASIC3's FIFO,
concerning the extreme size conversions (16in, 1out) or/and
the Empty flag, please step up ! If one of them is solved,
i'm saved
yg
--
http://ygdes.com / http://yasep.org