Epson TM-U295 Manual page 115

1 Host Requests Reverse Transfer.
2 Successful Negotiation to Another mode.
3 Peripheral Has Data To Send.
4 Peripheral Has No Data To Send.
5 Host Goes To Idle.
6 Peripheral Has New Data.
7 Peripheral Has Data Send.
8 Host Requests Data Byte.
9 Host Receives Data Byte.
Peripheral Has No More Data To Send. nDataAvail = High
10 Host receives Data Byte.
Peripheral Has More Data.
11 Host requests termination.
12 Interface Returns To The Compatible Mode.
* In states other than in the process of data acception, the interface is set in the Forward Idle
phase.
H.1.2.1 Phases in Compatibility Mode
ù
Compatibility Mode Forward Data Transfer phase:
This phase allows the printer to accept data from the host.
perform handshaking in response to the signals, nStrobe, nAck and Busy.
not initiate any negotiation phase to a new operating mode until the interface successfully
returns to the Compatibility Mode Forward Idle phase.
ù
Compatibility Mode Forward Idle phase:
The interface is in Compatibility Mode, with no data transfer in progress.
allowed to initiate a data transfer in Compatibility Mode, or initiate negotiation phase to a
new operating mode.
H.1.2.2 Phases in Nibble Mode and Byte Mode
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Reverse Data Transfer phase:
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Reverse Host Busy Data Available phase:
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Reverse Host Busy Data Not Available phase:
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Reverse Idle phase:
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Reverse Interrupt phase: This phase makes the printer report to the host that it has got data to
EPSON
HostBusy = Low
Data transfer from the printer to the host.
The printer has data to transmit to the host.
The printer has no more data to transmit.
No data transfer is in progress and the host is waiting for the printer data.
When any printer data is available, the printer will cause the interface to go
to the Reverse Interrupt phase.
transfer in the Reverse Idle phase.
cause the interface to go to the Termination phase.
TITLE
TM-U295/U295P
Specification
(STANDARD)
nDataAvail = Low
nDataAvail = High
nDataAvail = Low
While in this phase, the host may
SHEET
REVISION
F
The host and the printer
The host shall
The host is
NO.
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App.20 App.19