not without troubles.
At 57600 Baud I get about 80m (through cat-5e cable) before the cable's capacitance becomes a significant load on the serial port's drivers.
the fix (which I devised) is to put an LED and 1N914 in series on the far end so that it conducts while the line is idle.
That way there's less charge needed to bring the line high.
impedance mismatch
Bye. Jasen
If you're going to bastardize the interface why not just get a driver that's designed to do the job?
I don't get to design the devices, but every so often I google to see if there's something better available.
at the weak end it's a PC serial port, the max-232 (or similar) on the far end has no trouble pulling the line high enough (I guess that'd be because in the worst case all that's between VCC and the high side output driver is a forwards biased diode)
Bye. Jasen
f
I do it all the time.
I use 9600 Baud which is more than fast enough for the application.
Use can use a stronger driver and still be in compliance.
Although that is a bit of a violation, it does work. If you roll your own driver, you can make it so that is sort of does this its self.
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