Star Micronics NP-225 - Manual (Page 14)

11
7) Timing chart
POWER
T2 T3
DATA
/STB
BUSY
T1 T4 T5 T6
/ACK
T1 = 3500msec (Max) T4 = 500nsec (Max)
T2, T3 = 500nsec (Min) T5, T6 = 4microsec(TYP)
8) Receive control
When BUSY signal stays at LOW, it is feasible to receive data from host computer.
But not feasible when BUSY signal stays at HIGH.
3.2 Serial interface (RS-232C)
1) Synchronization : Asynchronous
2) Transmission speed: 4800, 9600, 19200, 38400bps (user selectable)
3) A word consists of
Start bit : 1bit
Data bit : 7 or 8 bit (user selectable)
Parity bit
: odd, even or no parity (user selectable)
Stop bit : more than 1 bit
4) Signal polarity
RS-232C
Mark = Logic “1” (-3V -- -12V)
Space = Logic “0” (+3V -- +12V)
5) Receive data (RD signal)
RS-232C
Mark = 1
Space = 0
6) Reception control (DTR signal)
RS-232C
Mark = 1
Space = 0
7) Transmission control (TD signal)
DC1, [11]h XON: Enable data receiving
DC3, [13]h XOFF: Disable data receiving