Figure 5.28 Carriage Drive 1/2-Phase Excitation At Low Speed; Figure 5.29 Carriage Drive 2-Phase Excitation At High Speed - Digital Equipment LA30 N Service Manual

Figures 5.28 and 5.29 show 1/2-phase and 2-phase excitation.
SPI1, 2
SPM0
(φA)
SPM1
(φB)
SPM2
(φC)
SPM3
(φD)
Drive
phase

Figure 5.28 Carriage drive 1/2-phase excitation at low speed

SPI1, 2
SPM1
(φA)
SPM2
(φB)
SPM3
(φC)
SPM4
(φD)
Drive
D A A B C D A B C D A B C D A B C D A B C D A B C
phase
A D B C D A B C D A B C D A B C D A B C D A B C D
Figure 5.29
5-30
Idle
A A B B C C D D A A B B C C D D A A
B C
Carriage drive 2-phase excitation at high speed
Operating
D A B C D A B