Yamaha Portable Grand DGX-630 Service Manual page 42

DGX-630/YPG-635
TEST
LCD Display
No.
44 044 Rom Chk2
45 045 Ram Chk2
46 046 Flash RomChk2
47 047 Wave RomChk2
49 049 Factory Set
50 050 Test Exit
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42
Test Descriptions, Judging Criteria
Checks the ROM that is connected to the CPU bus.
The test result appears on the LCD. Make sure that "Rom OK" is displayed on the LCD.
It takes about 3 seconds.
(OK:"Rom OK", NG:"Rom NG")
Check the RAM that is connected to the CPU bus.
The test result appears on the LCD. Make sure that "Ram OK" is displayed on the LCD.
(OK:"Ram OK", NG:"Ram NG")
Checks the flash ROM that is connected to CPU bus.
The test result appears on the LCD. Make sure that "Flash Ram OK" is displayed on the LCD.
It takes about 30 seconds.
(OK:"Flash Rom OK", NG:"Flash Rom NG")
Checks the wave ROM that is connected to CPU bus.
The test result appears on the LCD. Make sure that "Wave Rom OK" is displayed on the LCD.
It takes about 40 seconds.
(OK:"Wave Rom OK", NG:"Wave Rom NG")
All backup domains are initialized and it changes into a factory-shipments state when executing
this test. It takes about 2 seconds.
Execute this to leave the test mode and change to the play mode.
Noise Level Check (in the normal mode)
Connect the level meter(with a JIS-C filter) to the [PHONES/OUTPUT] jack. (33Ω load)
Set the [MASTER VOLUME] at maximum and check that the noise level is within the range
below.
PHONES L/R : less than -74.0 dBu