Yamaha Portable Grand DGX-220 Service Manual page 31

TEST No. LCD Display
37 037 MIDI Chk
41 041 Rom Chk2
42 042 Ram Chk2
45 045 FRomChk2
47 047 Factory
48 048 TestExit
-- --
* Note: As for the test no.41 - 45, it takes time. If you want to skip them, press the [+/YES] button several times to go to the
test no.47 (Factory).
Test Descriptions, Judgment Criteria
Connect a PC which has installed the driver and main unit USB terminal with a USB cable.
Set the through mode on PC and execute the test.
Confirm that the C4 note is output and "MIDI OK" is displayed on LCD.
Checks the ROM that is connected to the CPU.
The test result appears on the LCD. Check that the LCD displays "Rom OK".
It takes about 15 seconds.
Check the RAM that is connected to the CPU.
The test results appear on the LCD. Check that the LCD displays "Ram OK".
Checks the flash ROM that is connected to CPU bus.
The check result appears on the LCD. Check that the LCD displays "FRom OK".
It takes about 30 seconds.
All backup domains are initialized and it changes into a factory-shipments state when executing
this test.
(While executing the test: "Fact --", After finishing the test: "Fact End)
Exit from the test program after executing this test.
Noise Level Check (in the normal mode) (33 ohm load)
Connect the level meter(with a JIS-C filter) to the [PHONES/OUTPUT] jack. (L and R)
Set the [MASTER VOLUME] at maximum and check that the noise level is within the range
below.
PHONES L/R: less than -78.0 dBu
DGX-220/YPG-225
(OK:"Rom OK", NG:"Rom NG")
(OK:"Ram OK", NG:"Ram NG")
(OK:"FRom OK", NG:"FRom NG")
31