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Configuring the AMM-1570/1572
AMM-1570/1572 User’s Guide
Stock Number:510526-00, Rev. B Page:2-1 3
Print Spec Number: 492379-00
Current Date: 3/7/94 ECN Date: 3/8/94
Synchronous Negotiation
Pin pair SN allows you to enable or disable whether the host adapter
initiates Synchronous Negotiation with a SCSI device. The available
settings are
Before data is transferred across the bus, the sending (initiating) and
receiving (target) devices negotiate and agree on how l ong each
piece of data is, and how many pieces are sent at a time—that is,
they agree on how fast to talk.
SCSI devices that support Synchronous Negotiation data transfer
can maintain a much higher conversation speed than devices that do
not support it.
When enabled, the host adapter initiates Synchronous Negotiation
with the SCSI device. When disabled, the host adapter does not ini-
tiate Synchronous Negotiation with the SCSI device. The host
adapter, however, always responds to Synchronous Negotiation ini-
tiated from the SCSI device.
If neither the host adapter nor the SC SI peripheral negotiate for
synchronous data transfers, all data transfers will be asynchronous.
Note: Some older SCSI-1 devices may have trouble han-
dling Synchronous Negotiation, which may result in
erratic behavior or a hang condition. For these d evices,
leave Synchronous Negotiation disabled.
SN
= Synchronous Negotiation Enabled
SN
= Synchronous Negotiation Disabled *
* = Default