Epson TM U200D - B/W Dot-matrix Printer Technical Manual page 67

Motor, paper feed drive circuit
The Motor, paper feed (stepping motor) possesses an accurate angle of rotation and permits
speed control. It is driven with 2-2 phase excitation. By turning P53 of the CPU to Low, +24V
(+24C signal in the figure below) is applied to the COM terminal of its coil, and it is made to run
by changing P90, P91, P92 and P93 to High and Low. Its speed is determined by the speed of
changing P90, P91, P92 and P93 between High and Low. At the end of paper feeding, P53 of the
CPU is once again set to High.
U5
56
P90/M10
58
P92/M12
57
P91/M11
59
P93/M13
+24C
Motor, carriage drive circuit
The Motor, carriage (stepping motor) possesses an accurate angle of rotation and permits speed
control. It is driven with 2-2 phase excitation. By turning P52 of the CPU to Low, +24V (+24B
signal in the figure below) is applied to the COM terminal of its coil, and it is made to run by
changing P20, P21, P22 and P23 to High and Low. Its speed is determined by the speed of
changing P20, P21, P22, and P23 between High and Low. At the end of paper feeding, P52 of the
CPU is once again set to High.
+24B
U5
52
P20/M00
54
P22/M02
53
P21/M01
55
P23/M03
2-26 Mechanism Configuration and Operating Principles
+5V
Q18
+5V
PF A/DSW5
Q19
D35
PF C/DSW7
Q20
D33
7
PF B/DSW6
5
Q21
3
1
D34
PF D/DSW8
D37
Figure 2-25 Motor, paper feed drive circuit
+5V
Q14
CR A/DSW1
Q15
CR C/DSW3
Q16
D30
CR B/DSW2
Q17
D31
CR D/DSW4
D36
Figure 2-26 Motor, carriage driving circuit
QM4 1
RM2
8 8 9
6
4
6 7
2
4 5
2 3
1 D10
0
+24C
+24B
D29
D9
QM3 1
RM1
7 8 8 9
5 6
3 4
6 7
1 2
4 5
2 3
1
0
Paper feed motor
CN6
(ROTOR)
1 PF A
1
2 PF C
2
3 PF COM
3
4 PF B
4
5 PF D
5
Carriage motor
CN5
(ROTOR)
1 CR A
1
2 CR C
2
3 CR COM
3
4 CR B
4
5 CR D
5
Rev.B