ER-A520U/ER-A530U HARDWARE DESCRIPTION
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5. A/D CONVERSION
In the ER-A520/530, the following three kinds of signals are inputted to
the A/D conversion port.
<CPU PORT>
5-1. PRINTER HEAD TEMPERATURE MONITOR
A voltage divided by the temperature detection thermistor of the printer
head and the resistor is inputted to AN0 pin.
The printer head conduction must be controlled as shown below.
5-2. PRINTER HEAD VOLTAGE MONITOR
A voltage is supplied by the printer head power source, passed through
the printer, and divided by the resistor is inputted to AN1 pin.
The A/D conversion value must be read after turning VHCOM signal
(CPU P106) to "H" and stabilizing the voltage (after 10msec).
The printable voltage range of the printer is 15V~26V. The voltage is
calculated from the AN1 value and the A/D conversion value of the ref-
erence voltage.
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
6. KEY/DISPLAY
6-1. LCD CONTROL
LCD control is same as the ER-A275P.
LCD-related Register
<CPU PORT>
When the read busy flag of the LCD display remains busy for more than
500ms, turn off LCDON (P121) for 1ms and perform initializing.
No. CPU PORT
Signal to
be used
Function
130 AN0 TM PRINTER HEAD TEMPERATURE
MONITOR
138 AN1 VPTEST PRINTER HEAD VOLTAGE MONI-
TOR
137 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 FOR CONDUCTION
TIME SPECIFIED ON PR-
58H CONTROL SPEC.
70°C or above 0~231 MOTOR LOCK
Function Address R/W
LCD Write Data 100001h W
LCD Read Data 100001h R
No. CPU PORT
Signal to
be used
Function
90 P120 BLON LCD BACK LIGHT ON SIGNAL
89 P121 LCDON LCD ON SIGNAL
88 P122 LRS LCD RS SIGNAL
87 P123 LR/W# LCD R/W# SIGNAL
86 P124 LE LCD E SIGNAL
85 P125 DATALE LCD WRITE DATA LATCH
P125: LWDL
L : LCD write data latch
P124: E
Enable Signal Enable
P123: R/W#
H: Data read L: Data Write
P122 LRS
H: Data input L: Instruction Input
LRS
LR/W#
LE
DB0-7
LWDL
DATA WRITE (CPU 3 LCD)
Valid Data
P122 "x"
P123 "L"
100001h
DATA
WRITE
P124 "H" P124 "L" P123 "H"
LRS
LR/W#
LE
DB0-7
LWDL
DATA READ (CPU 1 LCD)
Valid Data
P122 "x"
P123 "H"
P125 "H" P124 "H" 100001h
DATA
READ
P124 "L" P125 "L"
