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View Full Version : Serial communication to PC without a Max232



toalan
- 18th February 2005, 20:56
Okay I have tried using the serin and serout commands and have successfully used it to communicate to my laptop without a RS232 chip. My question is, since it works okay for my laptop would it be a safe to assume that it will work with 100% of all PCs?

mister_e
- 18th February 2005, 21:00
yes, in a short distance 10 feet or less. The MAX232 will provide a higher voltage swing wich is suitable for better distance and noise rejection.

NavMicroSystems
- 18th February 2005, 21:33
It depends . . .

Newer PCs with newer ChipSets are a bit more tolerant regarding the Levels on the COM-ports. (They might even accept TTL-levels on RX).

Some (older) PCs require levels of +/- 12V.

However:

Even if sending Data from a PIC to a PC works
you have got to take care when sending data from PC to PIC
as the the Levels on the PCs TX-pin might ecxeed the PICs limits.