Confidential
EPSON
TITLE SHEET
REVISION NO.
SHEETNEXT
21 20
TM-T88III series
Specification
(STANDARD) B
2.1.2.7 Reception of status from the printer through the bidirectional parallel interface
In the bidirectional parallel interface specifications, the printer status transmission is available by using
the both-way communication facility in the Nibble/Byte Modes in accordance with the IEEE 1284.
In this case, different from in the RS-232 serial interface specifications, the real-time interruptions from
the printer to the host are disabled and thus precautions must be taken to the followings.
1) Allowable capacity of the printer internal buffer is 99 bytes (except ASB status). The status
signals exceeding this capacity will be discarded. To prevent possible loss of status, the host
shall be ready for data acception (Reverse Mode).
2) When ASB is used, the host is preferably in the wait state for data acception (Reverse Idle Mode).
When this state is not available, the host shall enter the Reverse Mode to always monitor the
presence of data.
3) When ASB is used, preference shall be given to the ASB status for transmission over the other
status signals. Any accumulated ASB status signals left for transm ission from the last to the
newest ASB status transmission shall be transmitted together at a time as one ASB status
showing the presence of change, followed by the latest ASB status.
Example: In the normal (wait) state, the ASB status is configured as follows.
First Status Second Status Third Status Fourth Status
0001 1000 0000 0000 0000 0000 0000 0000
When a sequence of operations are proceeded, the near end is detected and
the printer cover is opened, then the printer cover is closed, the following
pieces of data are accumulated.
First Status Second Status Third Status Fourth Status
① 0001 1000 0000 0000 0000 0011 0000 0000 Near end detection
② 0011 1000 0000 0000 0000 0011 0000 0000 The printer cover is opended.
③ 0001 1000 0000 0000 0000 0011 0000 0000 The printer cover is closed.
When the ASB status is received following this, a total of eight (8) bytes of
ASB will be transmitted as follows.
Accumulated ASB (①+②+③)
First Status Second Status Third Status Fourth Status
Accumulated ASB (①+②+③)0011 1000 0000 0000 0000 0011 0000 0000
+ First Status Second Status Third Status Fourth Status
The latest ASB (③) 0001 1000 0000 0000 0000 0011 0000 0000
Fourth Status
2.1.2.8 Notes on setting DIP switch 2-1 to ON
Refer to Section 2.1.1.6.