3-6
3.3.3 Excitation
Sequence
Drive the motor with 2-2 phase excitation. One step of the motor drive signal feeds the paper 0.0625 mm.
One dot line is consisted of 2 steps. When the voltage signal shown in Figure 3-5 is input to the motor drive
circuit shown in Figure 3-3, the printer feeds the paper in the normal direction when the motor is excited in
order of step 1, step 2, step 3, step 4, step 5, step 6, step7, step 8, step 1, step 2, . . . . , as shown in Table
3-3.
PH3
PH4
H
L
H
L
PH1
PH2
H
L
H
L
H
L
MCL1
*
1 dot line
START
STEP
1 dot line
1 dot line
*: Set MCL1 to “High” while the motor is driven.
Figure 3-5 Input Voltage Waveforms for the Sample Drive Circuit
Table 3-3 Excitation Sequence
Input signal
Output signal
PH1 PH2
PH3
PH4
A
B
A
B
Step
1 L H L L L H H L
Step
2 L L L L L L H H
Step
3 H L L L H L L H
Step
4 H H L L H H L L
Step
5 L H L L L H H L
Step
6 L L L L L L H H
Step
7 H L L L H L L H
Step
8 H H L L H H L L