STYLUS 800 Service Manual Operating Principles
2.3.2.4 Carriage Motor Drive Circuit
Carriage motor drive
IC
SLA7024
(IC13)
drives the carriage motor for the printer mechanism by a
I
constant current,
unipolar
drive system. Gate array
E05A85EB
(IC3)
selects the motor phase drive
current level using the output signals from ports
CRO
to
CR3
(pins 75 to 78). The phase switching
operation is directly controlled by
the
phase control signals output from ports
P600
to
P603
(pins 1
to
4)
of the CPU. The table below shows the carnage m-otor drive modes.
-
Table 2-6. Carriage Motor Drive Modes
CR
speed
Drive
Phase Acceleration
Normal/Deceleration
(CPS)
Frequency Excitation Current Current
(PPS)
(A/Phase) (A/Phase)
225
5400
1-2 phase
0.80 0.45/0.80
150
3600
1-2 phase
0.60 0.30/0.60
83 2000
1-2 phase
0.80 0.80
40 960
1-2 phase 0.45
0.30/0.45
HOLD
—
2 phase
Approx. 0.15
SLA7024MEL
(IC13)
CPU
P600
‘
6
INA
(ICI)
P601
2‘7INB
P603 3 5 IN-A
P602 4
16
IN.B
A
+5V -A
R59
B
WRM26
RFA
RM25
RFB
-B
E05A85EB
CRO
78 R33
(IC3)
CR1
77
R34
CR2
76
R35
CR3
-75
R36
CR
+35V
Motor
(CN6)
;
CRCOM
8
1
*
CRA
18
s
CR-A
11
b
CRB
—
CR-B
Figure 2-17. Carriage Motor Drive Circuit Block Diagram