[Discuss-gnuradio] ramping down (tx_empy continued)

[Brett Trotter]

I've been pondering a few ways to do the wait and ramp down (wait something
like 16 clocks and then ramp down by right shifting on each clock)- but to
do so, I need to know what the last value was so I can shift it. Will
tx_i_*/tx_q_* remain persistent between clocks (my deduction was yes?) If
so, my plan here was to have a reg that holds a 4-bit counter that starts at
15 whenever tx empty goes high/true and then just keep right shifting the
appropriate value (based on load_next) until zero (or just keep shifting
until data since 0 >> 1 = 0- would that save on logic?).

Then I had one question- is there ever a situation where we're out of data
for any number of channels, but there's still one transmitting (e.g. can
tx_empty ever be asserted when we're feeding just one of the 4
destinations?). I'm under the (mistaken?) impression that tx_empty asserts
when we stop feeding the buffer altogether (underrun)- so without doing some
digging- do we fill zero's to the channels we're not using when we're still
feeding one of them?

With those answered, I think I can probably try and get a version done today
for testing.
-- 
View this message in context: 
http://www.nabble.com/ramping-down-%28tx_empy-continued%29-tf3021634.html#a8392238
Sent from the GnuRadio mailing list archive at Nabble.com.