Programming the Propeller with a 4mHz crystal

LoopyByteloose

I am still waiting for parts from the U.S.A.; including several 5mHz crystals and the 24LC256s.

Until then, I am trying to jury rig a setup from what is on hand.
Will a 4mHz crystal down load programs or will this interfer with the timing?

I haven't gotten deep enough into the IDE to see how to select appropriate speed.

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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

Gadgetman

That shouldn't matter as the Propeller runs on the internal Fast RC-clock until Spin is started and some instruction there tells it to switch to another source.

In other words, as long as you don't tell it to switch to an external source, or mess with the PLL, it'll trundle happily along at 12MHz from the internal RC-clock.

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Don't visit my new website...

LoopyByteloose

Great. I am a bit surprised that it is stable enough for RS-232. I previously read that most RC clocks are consider to be about +/-7%, but serial communications needs are much tighter [noparse][[/noparse]maybe less than 3%].

I have my breadboard. complete with dual voltages except for the serial port set up.

I am going to try the Transistor setups first and then the MAX232 if they don't work.

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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

Tracy Allen

It does not use standard RS232 encoding. Chip and Jeff came up with a unique ratiometric encoding scheme, not sensitive to exact timing, that just happens to use the RS232 interface.

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Tracy Allen
www.emesystems.com

LoopyByteloose

Typically superb innovation from Parallax. It will take me another 5 years to comprehend though.

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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