Epson LQ-860 Technical Manual page 110

2.3.6.3 CR Motor Control
CR Motor Phase Switching System
The CR motor is a 4-phase stepper motor, and each phase is controlled by the corresponding terminal
to P03) of the CPU (4B) via the inverter (16). Two phase switching systems are used; 2-2 phase switching
and 1-2 phase switching.
One step of the 2-2 phase switching system corresponds to two steps of the 1-2 system. Figure 2-59 shows
the CR motor phase switching timing. Table 2-36 shows the relationship between the CR motor speed and
the phase switching system.
ON
1A
OFF
ON
IB
OFF
(1A)
ON
OFF
ID
OFF
\
Step
Rotat ion
ON
OFF
(1A)
ON
ON
ID
OFF
\
I
N
'
I 1
1
a)
1
I
2 3
1
b) 1-2 Phase Excitation
Figure 2-59. CR Motor Phase Switching Timing
I
I
I
I
I I
6
(Carriage moves left to right. )
Phase Excitation
2-2
I
I
4 5 6
(Carriage moves left to
2-63
I
1
I
1
1
7 8
I
1
1
I
I
I
7
right. )
(POO