Page 146 - Making PIC Microcontroller Instruments and Controllers

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E2 15 SHAREDWITH F^/1/ LINE
LCD
u10 R]2
3 J 1 0
2 6 -]1
B ,-)o
D t:
1
RS485
sN175176,4

c6
c7
fiffigS RS485 communications wiring. (Wiring diagtam for lhe RS 485
slandard.)

Usins the RS485 Communications

In order to use the RS485 serial communications standard (see Figure 8.2), pins must
be installed in JP4 to enable the ground connections and allow J10 to carry the com-
munications. As mentioned earlier. the RS232IC in U9 must be removed. After these
changes, the operations will be similar to the RS-323C standard.