D-F0390 NP-326 Product specifications Ver.0.02
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3. Interface specifications
3.1 Parallel interface (Centronics compliant)
1) Data input
: 8 bit parallel method(DATA 0 – DATA 7)
2) Control signals
: /ACK, BUSY, /STB, /ERROR, PE, SLECT
3) Input signal to a printer
DATA 0 – 7
: 8 bit parallel signal(positive logic)
/STB
: Signal to read 8 bit data(negative logic)
/LF
: Signal to feed paper to print mechanism(negative logic)
4) Output signal from a printer
/ACK
: Enquiry signal for 8 bit data. It’s also pulse signal which is output after
BUSY signals (negative logic)
BUSY
: Indicate BUSY status of the printer. Inputs new data at LOW status
(positive logic)
/ERROR
: This signal becomes LOW when a printer is in the alarm status.
In the LOW status, all control circuits in the printer stops (negative logic)
PE
: Outputs when roll paper becomes empty (positive logic)
SLCT
: Signal to indicate on-line status (positive logic)
5) Input/Output signal level
Standard value
Code
Min. TYP. Max.
Unit
Input low level
V
IL
- - 0.
8
V
Input high level
V
IH
3.25 - 5.25
V
Output low level*
V
OL
- - 0.7 V
Output high level
V
OH
3.25 -
- V
*I
OL
4mA
6) Input/Output Circuits conditions
VCC
10K
○
LF
IN PUT
VCC
VCC
74LV574
STROB
PD0~PD7
ACK, P E, SLCT, ERROR
BUSY
INIT IN
OUT PUT
OUT PUT
IN PUT
IN PUT
IN PUT
3.3K
100
470p
3.3k
3.3K
74LV14
74LV14
47
74LV32
47
1SS319
510
