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Introduction
SYM53C810A Benefits Summary
1-4
SYM53C810A Data Manual
I
T hree programmable SCSI timers: Select/
Reselect, Handshake-to-Handshake, and
General Purpose. T he time-out period is
programmable from 100
seconds
μ
s to greater than 1.6
I
SDMS software for complete PC-based
operating system support
I
Support for relative jump
I
New SCSI Selected As ID bits for use when
responding with multiple IDs
Flexibility
I
High level programming interface (SCSI
SCRIPT S)
I
Support for execution of tailored SCSI
sequences from main system RAM
I
Flexible programming interface to tune I/O
performance or to adapt to unique SCSI
devices
I
Flexibility to accommodate changes in the
logical I/O interface definition
I
Low level access to all registers and all SCSI
bus signals
I
Fetch, Master, and Memory Access control
pins
I
Support for indirect fetching of DMA address
and byte counts so that SCRIPT S can be
placed in a PROM
I
Separate SCSI and system clocks
I
Selectable IRQ pin disable bit
I
Ability to route system clock to SCSI clock
Reliability
I
2 K V ESD protection on SCSI signals
I
Typical 300 mV SCSI bus hysteresis
I
Average operating supply current of 50 mA
I
Protection against bus reflections due to
impedance mismatches
I
Controlled bus assertion times (reduces RFI,
improves reliability, and eases FCC
certification)
I
Latch-up protection greater than 150 mA
I
Voltage feed through protection (minimum
leakage current through SCSI pads)
I
25% of pins power and ground
I
Power and ground isolation of I/O pads and
internal chip logic
I
Symbios Logic TolerANT technology with:
I
Active negation of SCSI Data, Parity,
Request, and Acknowledge signals for
improved fast SCSI transfer rates.
I
Input signal filtering on SCSI receivers
improves data integrity, even in noisy
cabling environments.
Testability
I
Access to all SCSI signals through
programmed I/O
I
SCSI loopback diagnostics
I
SCSI bus signal continuity checking
I
Single-step mode operation
I
Test mode (AND tree) to check pin continuity
to the board