Service manual
EPSON Stylus Color 400 Service Manual
Rev.A
2-
8
The table below shows W1-2 phase drive sequence at each steps when the rotor of carriage motor
makes one rotation. In the Stylus Color 400, in addition to a function that printing is performed with W1-2
drive phase, high speed skip mode which is a function to skip over the blank from the end of the printing
data to the next data starting point with high seed can be also performed by 2-2 and 1-2 phase drive.
W1-2 phase requires 4 times as much steps as 2-2 phase drive, calculating 2-2 phase as standard.
By using this method, it becomes possible to supply constant stable torque to the motor. As a result, it
also became difficult to be influenced by vibration from the printer mechanism during printing.
Table 2-4. Motor Drive Sequence(W1-2 phase drive)
Sequence
Number
Phase A Phase B
Phase a 10a l1a Current
Duty
Phase b 10b l1b Current
Duty
0010+2/3010+2/3
1001+1/3000+1
2X110000+1
3101-1/3000+1
4110-2/3010+2/3
5100-1X01+1/3
6100-11110
7100-1101-1/3
8110-2/3110-2/3
9101-1/3100-1
10X110100-1
11001+1/3100-1
12010+2/3110-2/3
13000+1101-1/3
14000+1X110
15000+1001+2/3
This W1-2 phase drive (or 2W1-2 phase drive) is called Micro-step and is attached with so called
2/3 • Vref or 1/3 • Vref factor, compared with drive current value (Vref100%) which is supplied at 2-2phase
drive. This Micro-Step allows the rotor to have delicate rotation. In the 2-2 phase drive method, it is usually
required to take 4-step sequence in order to rotate the rotor once. However, in case of W1-2 phase, it is
required to take 16-step sequence(in the table 2-4, sequence 0∼15) which is 4 times more than 2-2 phase
method to do that. Also, in case of 2W1-2 phase drive which can be seen in the Stylus Color etc., it takes
2-step to rotate the rotor once. The table below shows relation of rotation direction of rotor and carriage
proceeding direction.
Table 2-5. Relationship Between Rotor Direction and Carriage Operation
Carriage proceeding
direction
Rotation direction of
Rotor
Drive method Proceeding order of
sequence
HP→80 column direction
Looking from rotor output
side, clockwise direction
2-2, 1-2, W1-2 phase
Sequence No.0→15
80 column→HP direction
Looking from rotor output
side, counterclockwise
direction
2-2, 1-2, W1-2 phase
Sequence No.15→0