Ziatech Corporation ZT 8809A, Руководство по эксплуатации

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Introduction
A performance increase over 8088-based STD CPU boards is
achieved in part by the use of the NEC V20 microprocessor. This is
an 8088 compatible processor with a superset of the 8088 instruction
set. The V20 is a CMOS device with a standby mode, which results in
lower power consumption.
The ZT 8808A/8809A and 88CT08A/88CT09A boards also provide
an increase in memory capacity over the earlier non-"A" versions
(ZT 8808/8809 and 88CT08/88CT09). The "A" versions allow up to
640 bytes of static RAM directly on the processor board, thus
eliminating the need to use an additional memory board. Increased
memory capacity is accomplished by adding support for a 512 Kbyte
RAM device in socket 7D1 and placing a 128 Kbyte RAM in
socket 3D1 (this configuration assumes no EPROM in socket 3D1). If
you have been using an additional memory board (ZT 8824,
ZT 8820B, ZT 8825, or other) to achieve 640 Kbytes of system RAM,
you may be able to eliminate that memory board from your system by
putting more system RAM on the "A" version processor board.
However, systems with large RAM and PROM disks on the ZT 8825
will probably still require the ZT 8825.
Peripherals on the ZT 8808A and ZT 8809A include three
counter/timers, an interrupt controller, a real-time clock, two
RS-232-C serial ports (one of which may be configured to be
RS-485), a Centronics printer interface or general purpose parallel I/O
port, and four 32-pin memory sockets. The memory sockets may
include one EPROM, two RAM, and one additional RAM or EPROM
(the last socket is configurable). An additional 32 Kbytes of on-board
RAM and a general purpose LED indicator are also provided.
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