NEC VERSA P, Service Manual

Page: 28 / 177

Technical Information 1-13
PARALLEL INTERFACE
The system's parallel interface integrates National’s PC87332VLJ chip. It uses a 25-pin D-
subconnector that is Enhanced Capabilities Port (ECP) equipped. The port is located on the
system's rear panel.
The user selects between three parallel interface modes using Auto Setup. These include
unidirectional, bidirectional or enhanced. Unidirectional mode sends data output from the
standard ISA port only. Bidirectional mode sends data using the standard ISA port or PS/2
technology. Enhanced mode enables high speed data transmission to occur using either the
unidirectional or bidirectional modes.
The parallel port address is 378h and the interrupt level is IRQ07. Pin locations for the par-
allel interface are listed in Appendix A.
SERIAL INTERFACE
The RS-232C serial port is a 9-pin connector on the system’s rear panel. The serial port
consists of a 16550 compatible serial port controller with a programmable baud rate within
50/56000 bps. The serial port connects an RS-232C device or an external modem. The se-
rial port address is 3F8h and the interrupt level is IRQ04.
VERSA P SERIES CHIP SET
Refer to Table Section 1-6 for a quick summary of the chip types used in the system. See
the Abbreviations section at the beginning of this manual for a translation of chip technolo-
gies.
Table Section 1-6 Versa P Series Chip Types and Technologies
Chip Manufacturer Description Technology
P54C Intel 75 MHz CPU 320-pin TCP
PT86C868/
PT86C718 Pico Power System Logic 144-pin TQFP/
176-pin TQFP
N28F020-150 Intel 256k x 8 Flash ROM 32-pin PLCC
PT86C718 Pico Power IDE Interface, Peripheral
Controller, Interrupt
Multiplexer 176-pin TQFP
C&T65545 Chips &
Technologies VGA Controller 208-pin QFP
PC87334VJG National
Semiconductor Diskette Controller, IDE,
Parallel Interface 100-pin TQFP
M38802M2-001HP Mitsubishi Keyboard Controller
64-pin TQFP
CL-PD6720-B-2 Cirrus Logic PCMCIA Controller 208-pin QFP