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Chapter Five
Eagle 450 Upgrade Instructions, Rev. A00
For example, if the QUEUE statement in your system initialization command file is currently set
to 200 and the JOBS statement is set to 50, the resulting formula would look like this:
New Queue Block Requirement = 200 + (13 x 50)
This example results in a setting of 850 queue blocks. However, we strongly recommend that
you use a minimum a 2,500 queue blocks, even if the formula results in a lower number.
5.
Since you will be booting from a SCSI disk drive connected to the AM-138 board, you need to
define the SCSI dispatcher for the Eagle 450 (described in Chapter 3) in the system initialization
command file. Add this command to the INI file after the JOBALC statements, but before the
first DEVTBL statement:
SCZDSP SCZ138.SYS
For example:
:T
JOBS 1
JOBALC JOB1
;
TRMDEF TERM1,AM318=0:19200,AM62A,100,100,100,EDITOR=15
VER
SCZDSP SCZ138.SYS/ET
;
DEVTBL DSK
The SCZ138 dispatcher supports several option switches, as shown in the following table:
Switch
Description
/ET
Enable tolerant active negation
/EW
/EW:{id#}
Enable Wide SCSI negotiation for all devices
Enable Wide SCSI negotiation for SCSI device ID#
/NQ
/NQ:{id#}
Disable Command Queuing for all devices
Disable Command Queuing for SCSI device ID#
/NS
/NS:{id#}
Disable Synchronous Negotiation for all devices
Disable Synchronous Negotiation for SCSI device ID#
/NP
Disable Parity Checking (Parity still generated) on all devices
Table 5-1: Dispatcher Switch Table
We recommend that all Eagle 450s use the /ET switch (as shown above) to enable tolerant active
negation. Using active negation improves bus integrity when using synchronous data transfers.
Never attach a device to or remove a device from the SCSI bus while system power is
on. This is never a good idea, but active negation makes it even more likely that doing so
will damage the device, the SCSI controller, or both.
