Epson TM-U295

EPSON
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TM-U295/U295P
Specification
(STANDARD)
App.19App.20
1 Host Requests Reverse Transfer.
2 Successful Negotiation to Another mode.
3 Peripheral Has Data To Send. nDataAvail = Low
4 Peripheral Has No Data To Send. nDataAvail = High
5 Host Goes To Idle. HostBusy = Low
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. nDataAvail = Low
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. The host and the printer
perform handshaking in response to the signals, nStrobe, nAck and Busy. The host shall
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. The host is
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
ù Reverse Data Transfer phase:
Data transfer from the printer to the host.
ù Reverse Host Busy Data Available phase:
The printer has data to transmit to the host.
ù Reverse Host Busy Data Not Available phase:
The printer has no more data to transmit.
ù Reverse Idle phase: 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.
ù Reverse Interrupt phase: This phase makes the printer report to the host that it has got data to
transfer in the Reverse Idle phase. While in this phase, the host may
cause the interface to go to the Termination phase.