Table 2-5. Cr Motor Drive Sequence - Epson C117001-N - DFX 5000+ B/W Dot-matrix Printer Service Manual

Left -+ Right
Right + Left
PI control keeps the carriage motor speed constant using the following steps:
"
1. CN1O outputs two encoder pulses (ENC-A and ENC–B) to thegatearray.
2.
3. The CPU outputs the PWM (pulse width modulation) signal according to the carriage motor
speed to the PWM port of the gate array and determines the duty of the carriage drive timing.
CR ports A, B, and C output the drive signal for the CR motor.
4.
Until the carriage speed reaches the constant speed set by PI control, acceleration control
determines the speed of the carriage. The printer can print while the carriage is accelerating. The
carriage speed moves to constant control speed smoothly to prevent the CR motor from exceeding
the constant control speed. 'l'he E05A87 gate array controls the motor driver (SLA5007), which
performs the current chopping. Figure 2-24 shows the acceleration control curve.
Note: In Figure 2-24, the acceleration curve is labeled A and the driving modes are labeled B.
Rev. A

Table 2-5. CR Motor Drive Sequence

Driving Mode
Acceleration
Deceleration 1
Deceleration 2
Deceleration 3
Acceleration
Deceleration 1
Deceleration 2
Deceleration 3
o
B
Driver (Refer to Figure 2-22.)
Q1
On
on
on on
On On
On
Operating Pdncipbs
04
On
on
on
on
2-27