Minimig Shared RS232

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Revision as of 12:03, 27 July 2007 by Freqmax (talk | contribs) (rs232 fix)
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By wiring the MCU (PIC18) and the fpga via an AND gate one can eliminate the jumper currently present on the rs232 TxD.

RS-232:
Default voltage level is negative (-3 .. -25) = Logical "1"

Truth table: 00 0 01 0 10 0 11 1

http://en.wikipedia.org/wiki/Rs232#Voltage_levels http://www.winpicprog.co.uk/pic_tutorial7.htm