Fujitsu M3097G Manuel D’Utilisation

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4.4.11 READ command
The following table shows the normal sequence of the READ command when used
with this scanner.
Step
Bus phase
Initiator operation
¨ Æ
Target operation
1
BUS FREE
Verifies bus free
2
ARBITRATION
Obtains bus>usage
right
3
SELECTION
Selects target
Æ
Drives BSY signal
4
MESSAGE OUT
Selects logical unit
Æ
5
COMMAND
Specifies READ
(CDB)
Æ
Reads document
6
DATA IN
¨
Transfers image data
7
STATUS
¨
Reports GOOD status
8
MESSAGE IN
¨
Reports message (Command
Complete)
Releases BSY signal
9
BUS FREE
(1)
READ command:   COMMAND phase  (initiator Æ target)
The READ command is used by an initiator to request a target for transfer of data.
Upon receiving this command, the target returns scan data to the initiator. 
The CDB of this command is shown in the following illustration.
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