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Are we already at 80Mhz on the A9 123 board? — Parallax Forums

Are we already at 80Mhz on the A9 123 board?

Just got setup. Thanks Chip and Parallax. This one looks like it works great.

Ran my test code, and got what looks like a mess on the screen. On a guess, I tried 80Mhz as the base for the timing calcs, and it all appears to work just fine.

?!?

Comments

  • Yep, 16 cogs @ 80 MHz = :):):)
  • Whoopee!!

    I'm unclear on the DAC differences. NTSC signal appearing on all DAC connectors. I'm not sure my DE2 did that. Never got my A7 to work, so I can't compare.

  • That's right for all the Dac's to show the signal.
    From the docs streamer modes
    dddd
    1111 X3 X2 X1 X0 output X3, X2, X1, X0 on all four DAC channels
    
  • cgraceycgracey Posts: 14,133
    edited 2015-11-27 05:40
    On the latest compiles, DAC channel 0 does not go out to a DAC, but its LSB goes out digitally as the HSYNC signal on the VGA connector. DAC channels 3/2/1 are R/G/B.
  • potatoheadpotatohead Posts: 10,253
    edited 2015-11-27 07:10
    I just found that out by changing modes. Mode %0100 results in only the sync being displayed. No signal, no borders, etc... neat!

    Hey, I'm having trouble understanding how to calculate xfr values.

    This: f_color / f_clock * float($7FFF_FFFF) * 2.0

    What is "float($7fff_ffff)" Is this a floating point hack for a shift operation?

    I'm wanting to do some scaled integer math to compute signal timings...

    Basically, I want to put this stuff into Excel, figure out the math, then do PASM to get away from the constants. Did the same thing on P1 to validate a lot of signals.

  • ok guys, how do I get me one of these A9 boards?
  • cgraceycgracey Posts: 14,133
    potatohead wrote: »
    I just found that out by changing modes. Mode %0100 results in only the sync being displayed. No signal, no borders, etc... neat!

    Hey, I'm having trouble understanding how to calculate xfr values.

    This: f_color / f_clock * float($7FFF_FFFF) * 2.0

    What is "float($7fff_ffff)" Is this a floating point hack for a shift operation?

    I'm wanting to do some scaled integer math to compute signal timings...

    Basically, I want to put this stuff into Excel, figure out the math, then do PASM to get away from the constants. Did the same thing on P1 to validate a lot of signals.

    I was trying to mutiply by $1_0000_0000
  • evanhevanh Posts: 15,126
    ok guys, how do I get me one of these A9 boards?

    You've probably already got an answer but the original announce was here - http://forums.parallax.com/discussion/comment/1355129/#Comment_1355129
  • ok guys, how do I get me one of these A9 boards?
    I think the A9 boards went out to the people who bought A7 boards. The idea was to swap out all of the A7 boards for A9 boards. I suppose the A9 boards are probably for sale as well, maybe for the same $375 that the A7 boards sold for.

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