Protocols and computer networks, by Dr. D. Koren of Tel-Aviv University.

Documentation with download.

For RS485, RS422, RS232 and RS423.

RS-232 was created for one purpose, to interface between data terminal equipment and data communications equipment employing serial binary data interchange.

Describes interfacing the Serial (RS-232) Port in relation to both Hardware and Software. Gives Practical Examples using CDP6402 UART and Software Examples in C.

RS232 - overview of RS-232 standard - HW serever, serial, interface,

RS-232 Serial Communications is not that hard.

Tutorial discussion of the RS232 (EIA232) standard with signal names, definitions, and examples.