Centronics-Compatible Parallel Interface - GRAPHTEC CUTTING PRO FC3100-60 Service Manual

2.10 Centronics-Compatible Parallel Interface

This eight-bit Centronics-compatible parallel interface is generally used for interfacing printers.
The input data signals are grouped into the eight bits of the DATA signals (DB0 to DB7), and each group
of eight DATA signals is followed by the input of an active-LOW STROBE signal. Upon receipt of the
STROBE signal, the plotter activates its BUSY signal, outputs an ACK signal, then reads the input
DATA signals to begin a cutting or plotting operation.
When the specified operation is completed, the plotter awaits the input of subsequent DATA signals.
Caution : The interface cable should be no longer than two meters.
Specifications
• While the parallel interface is used, data cannot be output from the plotter (that is, READ commands
cannot be used with the exception of the "BS" command).
• Synchronization method: Asynchronous transmission by handshaking based on STROBE and BUSY
signals.
Electrical characteristics
Based on TTL-level compatibility with the logic states below.
 "1" +2.2V or more 
Positive logic
 "0" +0.8V or less 
 "1" +0.8V or less 
Negative logic
 "0" +2.2V or more 
Input / Output Circuitry
DATA, BUSY
ERROR , ACK, STROBE
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FC3100-60 Service Manual
P/N53802-031T Rev. A