CBM-710/720/730/750User ’sMa nual
22 CITIZEN
8.3 Descriptionof Input/Output Signals(1) Input/Output Signals
a) Input Signals (To Printer)
*DATA : 8 bit parallel signal. (Positive logic)
*STB : A strobe signal for reading in 8 bit data. (Negativelogic )
*RESET :A signal which res ets the entire printer . (Negative logic. 1 msor more)
b) Output Signals (F rom Printer)
*ACK : This is a pulse signa l for requesting 8 bit da ta, issued at the end of a B USY signal.
(Negative logic)
*BUSY : This signal indicates that your printer is in a BUSY state. New data should be input
when this signal i s "LOW". (Positive lo gic)
*FAULT : When yourprinter is in an alarm state, this signal is "LOW". At this time,all control
circuits of your printer are interrupted. ( Negative logic)
*PE : Whenthe paper is near its end, this signal is issued. (Positive logic)
Note: An alarm conditionoccurs when the timingof the print head movement sensor is abnormal.
c) Power Source
*+5VDC : The same +5V output as that of the power source whicha ctuatesthe control circuits.
This should be less than 30 mA.
*GND : The common circuit ground.
*FRAMEGND : Equivalent to "case ground".