I´m going to build an interface using PIC12C508. But when I look at the schematic I wounder; Where do I connect Vcc? Can I connect this to the DB9 in some way, or do I need an external battery?
Pin 7 of the DB9 is the source for Vcc. This is an RS232 line and the voltage can be anywhere from 5 to 15 volts. You should use a zener to set to Vcc to 5 or 5.6 volts.
Dennis
Okay, now I understand! If I just connect all Vcc on the schematic together it will work! I misunderstood and though that I should connect an external Vcc to them.
Thanks!!