CXD1185CQ/CR
• Send Message
The CXD1185C changes the phase to Message In by making the SCSI bus MSG and I/O signals active
and the C/D signal inactive. The message bytes are then sent.
If there is more than one message byte or if the message must be sent all at once, the transfer byte
counter must be used.
• Send Status
The CXD1185C changes the phase to Status and sends the status byte to the initiator.
It makes the SCSI bus I/O and C/D signals active and the MSG signal inactive.
• Send Data
The CXD1185C changes the phase to Data In and sends the data bytes to the initiator.
It makes the SCSI bus I/O signal active and MSG and C/D signals inactive.
If more than one data byte must be sent all at once, the transfer byte counter must be used.
• Disconnect
Makes all SCSI signals inactive, except for the RST signal.
• Receive Message Out
The CXD1185C changes the phase to Message In and receives the message bytes from the initiator.
It makes the SCSI bus MSG signal active and the I/O and C/D signals inactive.
If there is more than one message byte or if the message must be received all at once, the transfer byte
counter must be used.
• Receive Command
The CXD1185C changes the phase to Command and receives the command bytes from the initiator.
It makes the SCSI bus C/D signal active and MSG and I/O signals inactive.
If the command bytes must be received all at once, the transfer byte counter must be used.
• Receive Data
The CXD1185C changes the phase to Data Out and receives the data bytes from the initiator.
It makes the SCSI bus MSG, C/D and I/O signals inactive and receive the data bytes.
If more than one data byte must be received all at once, the transfer byte counter must be used.
2-4. Commands valid in initiator status
The following commands are valid only in initiator 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.
In the case of data send commands, the transfer data must not be written before the command is written in
the command register.
Once the execution of a transfer command is commenced in initiator mode, handshaking on the SCSI bus is
terminated under the following conditions :
1. The ACK signal is in any status and if :
· a hardware reset is performed.
· the “Reset Chip” command is executed.
· the SCSI bus RST pin is driven.
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SONY [ SONY CORPORATION ]
