Ieee 1284 Bidirectional Parallel Interface (Parallel Interface Specifications) - Epson TM-T90 Specification

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2.1.2 IEEE 1284 Bidirectional Parallel Interface (Parallel Interface Specifications)

Copyright © 1994 by the Institute of Electrical and Electronic Engineers, Inc.
2.1.2.1 Compatibility mode
(data transmission from host to printer: Centronics-compatible)
1) Outline
Compatibility mode supports the compatibility with a Centronics parallel interface.
2) Specifications
Data transmission:
Synchronization:
Handshaking:
Signal levels:
Connector:
3) Switching between online and offline
The printer is not equipped with any online/offline switch. The printer is placed into offline status
in the following conditions:
1) When the power is turned on or until the printer becomes ready for data transmission after it
is initialized by the reset signal (nINIT) from the interface.
2) During the self-test.
3) When the cover is open.
4) During paper feeding using the paper FEED button.
5) When the printer stops printing due to a paper-end (in cases when empty paper supply is
detected by either the paper roll end detector or the paper roll near-end detector with a
printing halt due to a paper end enabled by ESC c 4).
6) During standby status for macro execution.
7) When a temporary abnormality occurs in the power supply voltage.
8) When an error has occurred.
2.1.2.2 Reverse mode (data transmission from printer to host)
The STATUS data transmission from the printer to the host proceeds in the Nibble or Byte mode.
• Description
This mode allows data transmission from the asynchronous printer under the control of the host.
Data transmissions in the Nibble Mode are made via the existing control lines in units of four bits
(a Nibble). In the Byte Mode, data transmissions are accomplished by making the eight-bit data
lines bidirectional.
Both modes cannot work at the same time with the Compatibility Mode, thereby causing half
duplex transmission.
NOTE: A signal name preceded by the letter "n" indicates active LOW.
EPSON
8-bit parallel
Externally supplied nStrobe signals
nAck and Busy signals
TTL compatible
ADS-B36BLFDR176 (Honda) or equivalent (IEEE 1284 Type B)
TITLE
TM-T90
Specification
(STANDARD)
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