CXD1185CQ/CR
• Assert SCSI Control
Outputs the value of the SCSI bus control register to the SCSI bus.
In initiator mode ACK and ATN signals can be asserted.
In target mode REQ, MSG, C/D and I/O signals can be asserted.
This instruction is only needed in program I/O transfer.
On program I/O, see 5-1.
• Deassert SCSI Control
Prohibits the content of the SCSI bus control register from being output to the SCSI bus.
Once the “Assert SCSI Control” command is executed, the SCSI bus control signal is output from the SCSI
bus control register until this command is executed.
Therefore, the drive of SCSI bus control signal must be prohibited depending on needs.
• Assert SCSI Data
Outputs the value of the SCSI data register to the SCSI bus.
However, data is not output in the following circumstances :
i) A phase change interrupt (PHC) is generated in initiator mode.
ii) In initiator receive mode (SCSI bus I/O signal is high).
iii) In target receive mode (SCSI bus I/O signal is low).
iv) The mode is neither initiator nor target.
This instruction is only needed in program I/O transfer.
On program I/O, see 5-1.
• Deassert SCSI Data
Prohibits the value of the SCSI data register from being output to the SCSI bus.
Once the “Assert SCSI Data” command is executed, the SCSI bus data signals are output from the SCSI
data register until this command is executed.
2-2. Commands valid in disconnected status
The following commands are valid only in disconnected status. If any of these commands are issued in any
other state, the CIP bit and the content of the command register are cleared immediately.
• Reselect
This command executes arbitration/reselection from disconnected status.
When this command is executed, the CXD1185C switches to the target mode.
Before issuing this command, the owner ID (OID2-0) and target ID (TID 2-0) values must be written in the
SCSI ID register.
• Select without ATN
This command executes arbitration/selection from disconnected status.
When this command is executed, the CXD1185C switches to the initiator mode. Before issuing this
command, the owner ID (OID2-0) and target ID (TID2-0) values must be written in the SCSI ID register.
• Select with ATN
This command executes arbitration/selection from disconnected status.
During selection the ATN signal is driven on the SCSI bus.
When this command is executed, the CXD1185C switches to the initiator mode. Before issuing this
command, the owner ID (OID2-0) and target ID (TID2-0) values must be set in the SCSI ID register. If,
after this command is executed, message-out phase is to be terminated, the “Deassert ATN” command
must be executed prior to the transfer of the last message byte.
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SONY [ SONY CORPORATION ]
