ER-A410/ER-A420
HARDWARE DESCRIPTION
– 10 –
4-2. HEAD CONTROL
HEAD: 864 dots in all Printable range
RECEIPT side 384 dots
JOURNAL side 384 dots
Related PORT
*
When turning off the printer power supply, make sure to turn
/STB1,2,3,4 to “H.”
*
Do not turn on without paper.
*
THERMAL HEAD power supply control: Turn ON when P81 = ”H”;
turn OFF when at “L.” (The power supply for HEAD and STEPPING
MOTOR is shared.) When printing is finished, (when the motor is
stopped), the power should be turned off.
*
Before printing or feeding paper, perform A/D conversion in 10 ms
after the printer head is turned on and make sure the voltage is sta-
ble.
5. A/D CONVERSION
The following three kinds of signals are inputted to the A/D conversion
port of the ER-A410/420.
<CPU’s PORT>
5-1. PRINTER HEAD TEMPERATURE MONITOR
The voltage divided by the resistor and the thermistor for detecting the
temperature of the printer head is inputted to AN0 pin. As shown below,
the printer head energizing is controlled.
5-2. PRITER HEAD VOLTAGE MONITOR
A voltage is supplied by the printer head power supply, passed through
the printer, divided by the resistor, and inputted to AN1 pin. Before
reading the A/D conversion value, turn the VHCOM signal (CPU P81) to
“H” and make sure the voltage is stable. Then read the A/D conversion
value.
The printable voltage range for the printer is 15V~26V. The voltage is
calculated from the AN1 value and the A/D conversion value of the ref-
erence voltage of AN2.
5-3. REFERENCE VOLTAGE
The reference voltage (2.495V
m
0.085V) generated by KIA431F is input-
ted to AN2 pin.
469 (DEC)
t
VREF
t
557 (DEC)
VREF 469 (DEC) corresponds to VREF = 2.41V at VCC = 5.25V
VREF 557 (DEC) corresponds to VREF = 2.58V at VCC = 4.75V
No.
CPU PORT
Signal to be used
30
TXD2
SO
29
RXD2
SI
28
CLK2
PCLK
93
P103
/STRB1
92
P104
/STRB2
91
P105
/STRB3
90
P106
/STRB4
89
P107
LATCH
21
P81
VHCOM
/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
Total 864 dots
No.
CPU PORT
Signal to
be used
Function
97
AN0
TM
PRINTER HEAD TEMPERATURE
MONITOR
95
AN1
VPTEST
PRINTER HEAD VOLTAGE MONI-
TOR
94
AN2
VREF
REFERENCE VOLTAGE
HEAD
TEMPERATURE
A/D CONVERSION
VALUE (DEC)
OPERATION
-10°C or below
929~1023
MOTOR LOCK
-10°C ~ 0°C
869~928
PRINT IN ENERGIZING
TIME AT 0°C
0°C ~ 70°C
232~868
PRINT IN ENERGIZING
TIME SHOWN IN PR-45
CONTROL SPEC
70°C or above
0~231
MOTOR LOCK