AT&T 3B2/300 Technical Reference Manual page 193

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CM521A DIFFERENTIAL SCSI HOST ADAPTER CARD
The CM521A Differential Small Computer System Interface (SCSI) Host Adapter Card provides a
differential connection to the industry standard SCSI bus. The SCSI bus is a SO-conductor bus that
supports a wide variety of mass storage peripheral devices. The CM521A Card supports
synchronous/asynchronous bus transfers and improved bandwidth across the Enhanced Input/Output
(EIO) bus with a peak transfer rate of 3.0 megabytes per second and a maximum bus length of
25 meters.
The CM521A Card is a single-width card measuring 6.5 inches wide by 7.4 inches deep.
Figure 2-58 shows the component layout of a typical CM521A Differential SCSI Host Adapter Card.
Connector pinout information is provided in Appendix B. The major components of the CM521A Card
are listed below:
• An INTEL 80186 Microprocessor
• 64K bytes of Static Random Access Memory (SRAM)
• 64K bytes of Erasable Programmable Read Only Memory (EPROM)
• A FUJITSU* MB87030 SCSI Protocol Controller operating at 8 MHz.
*
Registered trademark of FUJITSU Limited, Nakahara-Ku, Kawasaki, Japan
EQUIPMENT DESCRIPTION 2-169