OCPRF100 MP Server System Technical Product Specification

Revision 1.0

Noise margin minimum on the high level is 0.2 VDD.

8.3.3SCSI Controller

The SCSI controller selected for this backplane is an 8-bit SYM53C80S controller. Device selection is memory mapped at address FB00-FC00.

It is reset on power up and when reset is asserted to the backplane.

SYM53C80S access slows down the bus; it is recommended to pulse SAF-TE infrequently.

SAF_TE command processing is 2–10 ms. The following is a feature summary of the SCSI con- troller:

•Supports the ANSI X3.131-1994 standard.

•Parity generation with optional checking.

•No external clock required.

•Onchip 48 mA single-ended drivers and receivers.

•Functions in both the target and initiator roles.

•Direct control of all SCSI signals.

•Asynchronous data transfers of up to 5.0 MB/second.

•Variety of packaging options.

•SCSI protocol efficiency is directly proportional to the speed of the microprocessor.

•CMOS parts provide additional grounding and controlled fall times that reduce noise gen- erated by SCSI bus switching.

•SCAM level 1 and 2 compatibility.

8.4LVDS SCSI Termination

8.4.1LVDS Termination

The following is a list of the features of the LVDS SCSI termination.

Auto selection multimode single ended or low-voltage differential termination

2.7V to 5.25 V operation Differential failsafe bias

Thermal packaging for low junction temperature and better MTBF Master/slave inputs

Supports active negation

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