Citizen CBM-272, User Manual

Page: 55 / 157

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6.3 Input and Output Signals
6.3.1 Input and Output Signals
(1) Input signals to the printer
• DATA
: 8-bit parallel signal (Positive logic)
• STROBE : Strobe signal to read the 8-bit data (Negative logic)
• RESET : Signal to reset the entire printer (Negative logic); 1 ms or more
(2) Output signals from the printer
• ACK
: 8-bit data request signal. A pulse signal to be output at the end
of the BUSY signal (Negative logic)
• BUSY : Signal to indicate that the printer is busy. Input new data when
it is “Low.” (Positive logic)
• FAULT : Turned to “Low” when the printer has an alarm. At this time, all
the control circuits in the printer stop. (Negative logic)
• PE : Output if the printing paper has run out or is running out.
(Positive logic)
• SELECT : Set to “Low” if low voltage occurs (set with DSW1-5).
(3) Power source and the related
• GND
: Common ground for the circuits
6.3.2 Electrical Characteristics
(1) Input signal level
All the input signals are at the CMOS level.
High level --- 4.0 V at minimum
Low level --- 1.0 V at maximum
(2) Output signal level
All the output signals are at the CMOS level.
High level --- 4.5 V at minimum
Low level --- 0.1 V at maximum
(3) Input and output conditions
The STROBE and RESET input signals are pulled up at 10 k
Ω
, and the other
input signals at 50 k
Ω
, respectively.
[Printer Side] [Host Side]
All the output signals are pulled up at 50 k
Ω
. (except SELECT signal)
Vdd
Twist Pair Wire