Citizen Systems CBM-291 Parallel Interface, Precautions, Explanation of input / output signals

5.2 Precautions

1.For LED ERROR , there is a resister of 330 Ohm on the circuit side to make current value 10 mA. Please use LED which its voltage is approx. 2V. LED over 10 mA may break a control board.

2.Make sure to supply power to all pins of power supply for circuit and power supply for operation to keep required current capacity.

3.Serial interface equips a driver and receiver of RS-232C, make sure to use it at RS-232C level.

4.RESET terminal is pulled up by 3.3K Ohm. Make sue to make this terminal NC, when this terminal is not used.

5.Absolutely, do not carry use No.19, No.21 and No.40 pins. Since they are used for printer main unit. In case they are used, they may cause abnormality or break control board.

6 Parallel Interface

6.1 Specifications

Data input method	: 8 bit parallel signal (DATA0 - 7)
Control signals	: ACK, BUSY, STB, FAULT, PE, RESET

6.2 Explanation of input / output signals

DATA0-7	: 8 bit parallel signal (Positive logic)
STB	: Strobe signal to read 8 bit data (Positive signal)
RESET	: Signal to reset control board
ACK	: 8 bit data request signal. Pulse signal output at the end of the BUSY signal
	(Negative logic)
BUSY	: Signal to indicate BUSY state of the printer.Input new data for "LOW" (Positive logic)
FAULT	: Signal which is made "LOW" when printer is in alarm state.(Negative logic)
PE	: Signal which is output when paper runs out.(Positive logic)

CITIZEN 25