REV.-A
2.3.5 Printer Mechanism Control
This section describes following operating principles:
. Carriage Control Circuit and Software Control
● Paper Feed Control Circuit and Software Control
● Print Control Circuit
2.3.5.1 Carriage Control Circuit
The carriage mechanism of the printer is driven by the carriage motor. Reversing the motor rotation,
holding, and phase switching for the carriage motor are controlled by the 4-phase stepper motor drive
IC
 
(IC2A:
 STK6722HZ). This 
IC
 
(IC2A)
 is controlled by a gate array 
(IC3A:
 E05A15HA) which is controlled
by the CPU. The rotational speed of the carriage motor is controlled by another gate array 
(IC3A:
E05A16GA). This gate array 
(IC7A)
 also outputs the power-down signal (PD 1 ) that shuts off carriage
motor drive voltage Vu when a hardware error is detected. Figure 2-33 shows the block diagram of
the carriage motor control circuit.
CPU
P?7
(4B) 
PDO
m
m
GA
(E?5A 15H$)
CRC
-
m
CRD
*
m
(3A)
-
m
PD1
~
m
Pco
PC3
(7A)
GA
(E05A
 
16GA)
Figure 2-33. Carriage Motor Control Block Diagram
2-41