2p24 poll speed
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Hi,
Can anyone tell me the polling speed of the 2p24 (roughly)? I don't
have the equipment to easily find it out. As Parallex quote '12,000
instructions per second' and the polling is 'between BASIC commands'
can I assume it has 100microsecond sampling? Somehow I doubt it!
Then how quickly does jump occr with a POLLRUN?
TIA
Adrian
Can anyone tell me the polling speed of the 2p24 (roughly)? I don't
have the equipment to easily find it out. As Parallex quote '12,000
instructions per second' and the polling is 'between BASIC commands'
can I assume it has 100microsecond sampling? Somehow I doubt it!
Then how quickly does jump occr with a POLLRUN?
TIA
Adrian
Comments
If you do a simple loop like
aa:
goto aa
the poll speed for a BS2p would be about 110 microseconds.
Chuck
It depends on the instruction. On the BS2p, a HIGH 0 takes close to
41 microseconds, AUXIO takes 28 microseconds, while more involved
commands can take a lot longer, for example, SHIFTOUT with a one byte
argument takes 380 microseconds. The polling test is done in between
instructions, so the rate is quite variable depending on what your
program is doing. That 12000 instructions per second figure is some
kind of average, and I've always wondered what benchmark program
Parallax used to determine it.
If you need the shortest possible latency, and your program does not
have to be doing anything else at the time, then use POLLWAIT 8.
-- best regards
Tracy Allen
electronically monitored ecosystems
http://www.emesystems.com
mailto:tracy@e...
>Adrian,
>If you do a simple loop like
> aa:
> goto aa
>the poll speed for a BS2p would be about 110 microseconds.
>
>Chuck
>>Hi,
>>
>>Can anyone tell me the polling speed of the 2p24 (roughly)? I don't
>>have the equipment to easily find it out. As Parallex quote '12,000
>>instructions per second' and the polling is 'between BASIC commands'
>>can I assume it has 100microsecond sampling? Somehow I doubt it!
>>Then how quickly does jump occr with a POLLRUN?
>>
>>TIA
>>
>>Adrian