[SOLVED] output of serial (UART) pin of uC: CMOS or RS232??

[sunnystar]

what is the output of serial (UART) pin of pic uC? pin 25 RC6 Tx pin has TTL/CMOS output or RS232 output?? i mean the output of UART pin od pic16f877a is TTL/CMOS voltage or RS232 voltage?

 

[betwixt]

From the pin name I would guess you are referring to a PIC of some type. They are CMOS devices so the voltage levels are also CMOS but if you are using a standard 5V supply they will also match (or exceed) TTL levels as well.

RS232 is a voltage level specification for sending data over long wires. It will never come directly from a uC, you will always need a converter circuit to change the uC logic low to +12V and the uC logic high to -12V.

Brian.