Casio MG-500 - Page 23

10 TEST MODE
(1)
To
start
the
test
program,
connect
pin
17
of
CPU
to
the
ground.
Ss BPD7BC 10
Connected
Te
pin?
=
J
RES:
wire
GND
Then turn the power switch on.
(2) ROM/RAM TEST
If all the LEDs illuminate, ROM (UPD23C256EG) is faulty and, if CPU's built-in RAM is
faulty, all the LEDs flashes.
(3) Switch test
Each switches’ contacts are checked by turning on an off of the corresponding LEDs.
Set Guitar/MIDI switch on “Guitar/MIDI", Octave switch on “Normal”, Chromatic/
Program Change switch on “Chromatic”, and all the Microswitches on “OFF”.
The test should be done by the following order.
Switch Position LED.
b ON
5 OFF
# ‘ON
Octave
#
OFF
# ON
=
OFF
Prog. Change ‘ON
Chromatic/ Prog. Change OFF
Frourentt
Goerwe:
Prog.
Change
‘ON
Prog. Change OFF
Microswitches b # aaa
* Turn the switch [ SWi ON ON OFF OFF
oTeeimcencly
SW2__
ON
OFF
ON
OFF
nr
Sw3_ON
ON
‘ON
OFF
sw4 ON OFF OFF ‘ON
SW5__ON ON orF | on
SWE ON OFF ON ON
SW7__ON ON ON ON
swe ON. | Flash OFF OFF
sws ON OFF Flash OFF