1. Introduction
9
ZT 8904
The ZT 8904 is a highly integrated 386 EX single board computer. The board meets the
needs of a wide range of industrial control and processing applications by operating
stand alone, as a single master in an STD 32 architecture, or as a permanent or
temporary master in an STD 32 architecture.
ZT 89CT04
The ZT 89CT04 extends the ZT 8904 operating temperature range from 0 to 65º C to
-40º to +85º C. Except for the temperature variations, all other features of the ZT 8904
and ZT 89CT04 are the same. Unless explicitly stated otherwise, all references in this
manual to the ZT 8904 include the ZT 89CT04.
ZT 8903
The ZT 8903 is a more economical board that includes all the features of the ZT 8904
except those listed below. Unless explicitly stated otherwise, all references in this
manual to the ZT 8904 include the ZT 8903 as well.
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ZT 8904 supports an IDE drive option not available on the ZT 8903
•
ZT 8904 supports a multiprocessing option not available on the ZT 8903
•
ZT 8904 includes RS-485 support not available on the ZT 8903
•
ZT 8904 includes four serial ports and the ZT 8903 includes two
•
ZT 8904 includes 128 Kbytes of battery-backed RAM not available on the ZT 8903
Stand Alone
The ZT 8904 does not require an STD bus backplane to operate. The ZT 8904 is able to
operate stand-alone in many applications because of the large selection of the most
commonly needed peripheral devices. A power connector location and four mounting
holes are available for stand-alone operation.
STD 32 Single Master
The ZT 8904 supports additional memory and I/O through the STD bus. In an STD 32
architecture, data transfers are dynamically adjusted to support 8-bit and 16-bit boards.
STD 32 Multiple Master
The ZT 8904 can be configured to operate as a permanent master or as a temporary
master in a multiple master architecture. With this architecture, up to seven ZT 8904
boards share STD bus memory and I/O resources. The ZT 8903 does not support
multiple master operation.