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ROM-BIOS Installation of the Serial Ports
Normally, the ROM BIOS supports Serial 1 as the DOS COM1 device, Serial 2 as the DOS COM2 device, and so on. If you disable a serial port, and there is no substitute serial port in the system, then the
Serial Port Connectors (J11, J13)
Serial 1 and Serial 2 appear on connector J11; Serial 3 and Serial 4 appear on connector J13. Table 2– 11 gives the connector pinout and signal definitions for J11 and J13. Both connectors are wired the same.
In addition, the table indicates the pins to which each signal must be wired for compatibility with DB25 and DB9 connectors. The serial port pinout is arranged so that you can use a flat ribbon cable between the header and a standard DB9 connector. Split a