SX Sim truncating

BebopALot

I want to run my SX28 with a 5.120 MHz crystal oscillator. The SX Sim truncates it to 5MHz. As a result, my timing is off. Is there anything I can do to get the SX Sim not to do that?

Thanks, BBAL

LoopyByteloose

I imagine that you can ask Guenther to add code for such.
{I think it is in VisualBasic.}

Alternatively, you could try runing it 10 times faster and adjust your read outs by dividing by ten.
That would only give a ballpark figure as you would still be short by 0.200.

Maybe, and just maybe you can get it to operate at 512Mhz and divide by 100.

I am assuming that it won't accept plain old Hz as a number, only Mhz.

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"When all think alike, no one is thinking very much.' - Walter Lippmann (1889-1974)

······································································ Warm regards,····· G. Herzog [noparse][[/noparse]·黃鶴 ]·in Taiwan

Post Edited (Kramer) : 2/2/2006 12:05:15 PM GMT

Guenther Daubach

BBAL,

until now, SXSim used a long variable to hold the specified clock frequency - this is why it truncated all "odd" values - shame on me! This is fixed in the meantime, and will come with the next release soon.

Thanks for pointing out this bug!

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Greetings from Germany,

G

LoopyByteloose

How is that for response.
Thanks Guenther.
Since I also now know it will become available I can think of ways to use it too.

Please be sure to document the convience.

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"When all think alike, no one is thinking very much.' - Walter Lippmann (1889-1974)

······································································ Warm regards,····· G. Herzog [noparse][[/noparse]·黃鶴 ]·in Taiwan

BebopALot

Thanks for that reply - I can estimate it like Kramer said. I just wanted to make sure I wasn't doing something like picking a "wrong MHz" crystal or something crazy like that.

Thanks both to Geunther and Kramer.

-BBAL

LoopyByteloose

I just talk, G

Guenther Daubach

As a matter of fact, the MIDI baud rate of 32,000 baud can easily derived from even clock frequencies (much easier than "standard" rates like 38,400). I think this is why the guys who defined the MIDI standard have choosen this baud rate.

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Greetings from Germany,

G

PJMonty

G

LoopyByteloose

Ironicially, I always thought the opposite [noparse][[/noparse]That MIDI chose a special figure to make it hard for engineers to make a generic device]. Obviously, I hadn't done the math.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
"When all think alike, no one is thinking very much.' - Walter Lippmann (1889-1974)

······································································ Warm regards,····· G. Herzog [noparse][[/noparse]·黃鶴 ]·in Taiwan

Guenther Daubach

Peter,

yes, you are right - the MIDI baud rate is 31250, and not 32000 as I had stated before.

Well, now that we have an SX device that can be clocked at 50 MHz, instead of just 1 MHz, here are the typical constants for the "standard" SX UART VP @ 50 MHz to handle the 31250 MIDI baud rate:

baud_bit = 3
start_delay = 13
int_period = 200

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Greetings from Germany,

G