This section describes the particulars of performing I/O on the serial (RS-232) interface. If you have not read the general discussion of I/O presented in the "General Input and Output" section, you should do so before reading this section. HTBasic requires a driver before the serial interface can be accessed. The Getting Started Guide explains how to load the SERIAL driver, how to prevent conflicts with a serial mouse, how to use more than two serial ports, and how to set driver switches.
This section describes the handshaking used for ENTER and OUTPUT, and shows how to select between hardware and software handshaking. A long discussion is presented on cabling, communication parameters, and data formats. An in-depth, technical discussion of the RS-232 standard and its omissions is given. Pin assignments for standard connectors are listed. The register definitions for CONTROL, STATUS, READIO, WRITEIO, and the ENABLE INTR are presented.
