Emerson MVME147 User Manual
GENERAL INFORMATION
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1
Interrupt Structure paragraph in Chapter 4) or SCSI bus
activity is slowed down. Additional commands may be sent
to the SCSI firmware for a different peripheral device.
activity is slowed down. Additional commands may be sent
to the SCSI firmware for a different peripheral device.
$FFFE078E: FUNNEL COMMAND ENTRY
This entry point is used by applications that require multiple
interfaces to the SCSI firmware. Unlike the single user
command entry, you may issue commands anytime the
firmware does not require an RTE to be performed. If an RTE
is required, and you wish to send a command at the same
time, you may accomplish both by using the RTE entry
(described below). The use of the FUNNEL command entry
causes the FUNNEL module to examine the state of the SCSI
bus, determine if the bus is currently in use, and send the
command to the bus if it is not in use. If the bus is currently
in use, the FUNNEL module checks if the device is not busy
so it can preprocess or queue the command and return to the
caller with an intermediate status of $A002. This
preprocessed or queued command is processed and sent to
the SCSI bus when the bus is free.
interfaces to the SCSI firmware. Unlike the single user
command entry, you may issue commands anytime the
firmware does not require an RTE to be performed. If an RTE
is required, and you wish to send a command at the same
time, you may accomplish both by using the RTE entry
(described below). The use of the FUNNEL command entry
causes the FUNNEL module to examine the state of the SCSI
bus, determine if the bus is currently in use, and send the
command to the bus if it is not in use. If the bus is currently
in use, the FUNNEL module checks if the device is not busy
so it can preprocess or queue the command and return to the
caller with an intermediate status of $A002. This
preprocessed or queued command is processed and sent to
the SCSI bus when the bus is free.
$FFFE0794: COME-AGAIN ENTRY
Branches to FUNNEL entry. All the queued commands are
serviced in the interrupt service routine through software
interrupt.
serviced in the interrupt service routine through software
interrupt.
$FFFE079A: RTE ENTRY
The SCSI firmware notifies the user/caller that an RTE
instruction needs to be executed by the RTE bit (13) of the
returned status word. If this bit is 0, an RTE is required; if this
bit is 1, an RTE is not required (the SCSI firmware does not
execute the RTE instruction so as not to preempt a task in a
VERSAdos or SYSTEM V/68 environment). SCSI firmware
users may inherit an RTE from another caller because of the
multiple caller interface. When an RTE is inherited from
another caller, the use of the RTE entry may be required to
send down a new command before executing an RTE
instruction.
instruction needs to be executed by the RTE bit (13) of the
returned status word. If this bit is 0, an RTE is required; if this
bit is 1, an RTE is not required (the SCSI firmware does not
execute the RTE instruction so as not to preempt a task in a
VERSAdos or SYSTEM V/68 environment). SCSI firmware
users may inherit an RTE from another caller because of the
multiple caller interface. When an RTE is inherited from
another caller, the use of the RTE entry may be required to
send down a new command before executing an RTE
instruction.
Equipment Supported
The following list shows the controller type assignments for SCSI controllers
explicitly supported by the SCSI firmware, and the drives supported by each.
/f3Note, however, that Motorola does not necessarily endorse or recommend
explicitly supported by the SCSI firmware, and the drives supported by each.
/f3Note, however, that Motorola does not necessarily endorse or recommend