FUJITSU MCJ3230SS User Manual

Page 118

Host Interface

4-44

C156-E224-01EN

(6) MESSAGE REJECT message: 07h (I

→ T)

The message received most recently is invalid or unsupported.

(7) NO OPERATION message: 08h (I

→ T)

This message causes no operation.

(8) MESSAGE PARITY ERROR message: 09h (I

→ T)

This message notifies TARG that a parity error was detected in the last message,
in the last byte received by the INIT.

(9) BUS DEVICE RESET message: 0Ch (I

→ T)

This message instructs the clearing of all I/O operations (commands) being
executed or stacked in TARG. TARG performs initialization by clearing not only
I/O operations started by the INIT that sends this message but also all INIT I/O
operations.

(10) IDENTIFY message: 80h-FFh (I

←→ T)

Bit

LUN

This message specifies the device addresses (LUN) of devices (logical units) under
TARG control to establish I/O operation paths between INIT and TARG.

a. Bit 6: Disconnect Privilege

If INIT specifies this bit as 1, TARG can execute disconnection. If it specifies 0,
TARG cannot execute disconnection.

b. Bits 2 to 0: LUN

These bits specify a logical unit under TARG control.

c. Message function

After the SELECTION phase, INIT first sends this message to TARG to specify
the logical units to be used for I/O operation. Similarly, after the RESELECTION
phase, TARG first sends this message to INIT to specify the logical units to be
reconnected.

(11) SYNCHRONOUS DATA TRANSFER REQUEST message (I

→ T)

Byte

01h

03h

01h

This message defines the parameters for synchronous data transfer between two
SCSI devices. Transfer Period specifies the data transfer rate. REQ/ACK Offset
that can be specified for the ODD ranges from 0 to 15. If REQ/ACK Offset is 0,
asynchronous transfer is used.

REQ/ACK Offset

Transfer Period [4

× m (ns)]