Epson MX-80 Technical Manual page 33

The Printer has been adjusted so that the head driving pulse width becomes 0.4
msec when
+
24VDC is applied to the print head.
(b) Stepper motor driver
The stepper motor driver functions to amplify two two-phase excitation signals, as
well as to lower the applied voltage of each motor so that the motor is not exposed
to unwanted heat when it is not driven. Both the carriage and paper feed stepper
motors require a mean current of approx. 0.3A when they are driven by two two-
phase excitation signals. The carriage stepper motor operates at approx. 500 pulses
per second when the Printer performs normal character printing at 80 columns.
(9) Switches and indicators on control panel
The MX-80 has three switches and four indicators on its control panel. All the four indica-
tors are green LED's, while the three switches are of non-lock type. Refer to the MX-80
Operation Manual for detailed information on the functions of the respective switches
and indicators. The switches and indicators on the control panel are connected to the
ports of the LSI 8041 or 8049 and their operations are under the software control of the
LSI. Fig. 2.22 shows the locations of the switches and indicators on the control panel,
and Table 2.7 shows the 9 signal lines extending from the control circuit board to the
control panel.
Connector
Pin No.
1
2
3
4
5
6
7
8
9
Power Switch
IOND:l~FI
I PgftER 0
..... 0
RUDY
0
:I'ER
0
Control Panel
Fig. 2.22 Switches and Indicators on control Panel
Table 2.7 Signal Lines from Control Circuit to Control Panel
Signal Name Description of Signal
ON LINE LP Signal for illuminating ON LINE indicator
PE LP Signal for illuminating NO PAPER indicator
READY LP Signal for illuminating READY indicator
ONIOFF LINE SW ON LNE switch
FFSW FORM FEED switch
LF SW LINE FEED switch
GL Ground
+12
+
12VDC
BUZZER Buzzer
2-21
Color of Lead
Purple
White
Gray
Yellow
Orange
Blue
Black
Brown
Red
REV. A