Description Of Input/Output Signals - Citizen CBM-920II User Manual

5.3 Description of Input/Output Signals

(1) Input signal
• DATA 1 to DATA 8 . . . 8 bit parallel signal (positive logic)
• STB . . . Strobe signal for reading out data (negative logic)
• RESET . . . Signal for resetting the entire unit (negative logic 4 ms or more)
(2) Output signal
• ACK . . . 8 bit data signal for requesting data. ACK is issued at the end of the
BUSY signal (negative logic)
• BUSY . . . Signal indicating the printer is busy. Input new data when the signal
is in "LOW" condition (positive logic)
• PE . . .Signal that shows form cutting (positive logic)
• FAULT. . . . Signal that shows that trouble like mechanism alarm etc. occurred
(3) Other
• GND . . . Ground commonly used in the circuit
• FRAME GND . . . Frame ground (case ground)
(4) Timing chart
Busy signal timing: Clear timing can be selected by the memory switch.
ACK signal timing: The following kinds of timing can be selected by the memory
switch setting.
POWER
DATA
STB
BUSY
ACK
Busy signal timing: Clear timing can be selected by the memory switch.
ACK signal timing: The following kinds of timing can be selected by the memory
switch setting.
DATA
T2 T1
BUSY
Before
ACK
BUSY
Center
ACK
BUSY
After
ACK
— 29 —
DATA DATA
T3
T4
T5
T1: 2.0us MIN
T2: 500ms MIN
T3: 5us TYP
T4: 5us TYP
T5: 5us TYP