Printer Control - Sharp ER-A520 Service Manual

4. PRINTER CONTROL

The PR-58HM printer is employed.
4-1. STEPPING MOTOR CONTROL
The stepping motor is driven at a constant current by SMA7036M (made
by Sanken).
1step: 0.125mm, 1dot: 1step
Printing speed: 50mm/s
<CPU PORT>
No. CPU PORT
109 P10
108 P11
107 P12
106 P13
105 P14
104 P15
103 P16
102 P17
<DRIVING STEP>
RECEIPT MOTOR
Driver IC input (CPU output)
STEP RAS RBS RCS RDS /RPFA /RPFB /RPFC /RPFD
1 L H L
2 L H H
3 H L H
4 H L L
Driver IC input (CPU output)
STEP JAS JBS JCS JDS
1 L H H
2 L H L
3 H L L
4 H L H
* When the motor is stopped, rush conduction must be performed for
10ms in the same phase as the last excitation phase to turn off con-
duction to all the phases.
3 RAS~RDS and JAS~JDS are turned to "L".
Allow at least 30ms before boosting after stopping.
When boosting, rush conduction must be performed for 10ms in the
first excitation phase to start the motor by acceleration control.
Signal to be used
RAS
RBS
RCS
RDS
JAS
JBS
JCS
JDS
Motor drive signal
H ON OFF ON OFF
L ON OFF OFF
L OFF ON OFF
H OFF ON ON OFF
Motor drive signal
/JPFA /JPFB /JPFC /JPFD
L ON OFF OFF
H ON OFF ON OFF
H OFF ON ON OFF
L OFF ON OFF
ER-A520U/ER-A530U HARDWARE DESCRIPTION
4-2. HEAD CONTROL
HEAD: All864dot
Printable area:RECEIPT side, 360dot;
JOURNAL side, 360dot
Related PORT
No. CPU PORT
2 P95/CLK2
1 P96/TXD4
144 P97/RXD4
118
117
116
115
STB1#: 1~288dot: 288 dots in all
STB2#: 289~432dot:144 dots in all
STB3#: 433~576dot:144 dots in all
STB4#: 577~864dot:288 dots in all
* When turning off the printer power supply, make sure to turn
/STB1,2,3,4 to "H."
* Do not turn on the printer under paper empty state.
* During printing or paper feeding, after 10ms of turning on the printer
head power, A/D conversion must be performed to check that the
voltage is stabilized before starting the operation.
4-3. OTHER PORTS
ON
ON
No. CPU PORT
136
135
134
133
ON
PHUPS: "1" Head up
PRES : "0" Receipt paper end
ON
PJES : "0" Journal paper end
VHCOM: "1" Thermal head power control: On at "H" and OFF at "L".
Turn off the power conduction when printing is completed (the
motor is stopped).
– 10 –
Signal to be used
PCLK
SO
SI
P110 STRB1#
P111 STRB2#
P112 STRB3#
P113 STRB4#
Total 864 dots
Signal to be used
P103 PHUPS
P104 PRES
P105 PJES
P106 VHCOM