Specifications

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TM-U590 series
Specification
(STANDARD)
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) Specifications
Data transmission: 8-bit Parallel
Synchronization: Externally supplied nStrobe signals
Handshaking: nAck and Busy signals
Signal levels: TTL compatible
Connector: ADS-B36BLFDR176 (HONDA) or equivalent (IEEE 1284 Type B)
Reverse communication (Printer Host): Nibble or Byte Mode
(2) Switching between online and offline
The printer is not equipped with any online/offline switch. The printer is placed into offline status
in either of the followings:
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 FORWARD/REVERSE button.
5) When the power is out of range temporarily.
6) 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 is proceeded 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 (Nibble). In the Byte Mode, data transmissions are proceeded by making the eight-bits
data lines bidirectional.
The both modes fail to be proceeded concurrently with the Compatibility Mode, thereby
causing half duplex transmission.