NEC POWERMATE PRO2180 - SERVICE 1997, Руководство по обслуживанию

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Technical Information 1-13
I/O addresses and interrupt levels for the two channels are given Table 1-6. The interrupt
level is selectable via Setup to either IRQ3 or IRQ4. Software selectable base addresses are
3F8h, 2F8h, 3E8h, and 2E8h.
NOTE:
Any interrupts used for the built-in
serial ports are not available for ISA parallel
ports.
Table 1-6 Serial Port Addressing and Interrupts
Starting I/O Address Interrupt Level Port
3F8h IRQ04 COM1
2F8h IRQ03 COM2*
3E8h IRQ04 COM3
2E8h IRQ03 COM4
* Used for IrDA data transfer
See Section 2 of the PowerMate Pro2200/2180 Service and Reference Manual for
information on resetting the port through the Setup Utility.
Serial interface specifications include:
„
Baud rate up to 19.2 KB per second
„
Word length - 5, 6, 7, or 8 bits
„
Stop bit - 1, 1.5, or 2 bits
„
Start bit - 1 bit
„
Parity bit - 1 bit (odd parity or even parity).
Serial interface signals are output through the system board’s 9-pin, D-subconnector. The
connectors are located at the rear of the system unit. Pin locations for the serial interface
connector are shown in Appendix A of the PowerMate Pro2200/2180 Service and
Reference Manual.
USB Interface
The Universal Serial Bus (USB) port allows you to add new plug and play serial devices
without opening up the system. You simply plug the devices into the port. The USB
determines system resources for each peripheral and assigns them without user intervention.
Up to 127 devices can be daisy chained to a single computer.