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Old 07-31-2014, 02:03 AM   #862 (permalink)
Astro
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Quote:
Originally Posted by MPaulHolmes View Post
The power section is identical in this case. What is the normal output voltages for tx and rx for the outside world? I've never checked.
Wiki says "Valid signals are either in the range of +3 to +15 volts or the range −3 to −15 volts with respect to the ground/common pin; consequently, the range between −3 to +3 volts is not a valid RS-232 level."
However some devices won't work with levels as low as +- 3v.
Normally there would be a MAX232 chip or equivalent in the circuit that takes logic voltage levels and makes the +- 12v signals.
I think flores would like access to the logic level (3.3v) rather than the +-12v.
So maybe a header with the logic level rx, tx and gnd seperate to the header with the rs232 compatible +- 12v signals.
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