81
MEP-7000
5
6
7
8
5
6
7
8
A
B
C
D
E
F
Check the voltage (V+1R2BD) of
the SOUTH CPU (IC202).
If power is not supplied, check the connection
of the power line.
If the SOUTH CPU, FLASH IC, or SDRAM is judged as
N
G
If the AUDIO DSP is judged as
N
G
DRIVE UNIT
No.
Waveform
Items for check
Causes and measures
Points to be checked
1
Check that RST# is H.
Check that the clock waveform
(24.576 MHz) signal is input to
the SOUTH CPU (IC202).
If it is not, the RESET IC (IC200) may be
defective or improperly soldered. If the
problem is not resolved after it is resoldered,
replace the IC.
2
SOUTH CPU
/FLASH IC
/SDRAM
AUDIO DSP
If the problem is not resolved
even after the above-mentioned
measures are taken.
Replace the SMAI
N
Assy.
If the problem is not resolved
even after the above-mentioned
measures are taken.
Replace the AUDIO DSP (IC501).
6
-
3
Check if the waveforms for the
data bus and address bus
fluctuate between H and L.
If the waveforms do not fluctuate, communica-
tions among the flash memory (IC205), SDRAM
(IC206/207), and the SOUTH CPU (IC202) may
not be established. Check the mounting status
of the pins of ICs which are linked through the
bus.
• SOUTH CPU(IC202)
• FLASH MEMORY(IC205)
• SDRAM(IC206/IC207)
• FPGA(IC301)
• USB CO
N
TROLLER(IC706)
-
-
-
5
1
Check the voltage (V+1R25DD)
of the AUDIO DSP (IC501).
If power is not supplied, check the connection
of the power line.
1
Check that the clock waveform
(16 MHz) signal is input to the
AUDIO DSP (IC501).
2
Check the waveforms of signals
between the SOUTH CPU
(IC202) and the AUDIO DSP
upon startup.
Signals output from the SOUTH
CPU (IC202):
• DSPRST#
• SPIOUT
• DSPCS#
Signals output from the AUDIO
DSP (IC501):
• SPII
N
• DSPDREQB#
If the waveform of a signal on the communica-
tion line upon startup is abnormal, check the
mounting status of the terminal on the output
side of the signal. If it is properly mounted, the
port connector may be damaged. Replace it.
3
-
4
1
33
34
5
1
Check if the clock signal (100
MHz) is output from the SOUTH
CPU (IC202). Also check if this
clock signal is input to the
SDRAM (IC206/IC207).
If the clock signal is output from the SOUTH
CPU but not input to the SDRAM, check if
connection is properly made. Correct any poor
connection you find.
If the clock signal is not output, go to [27].
4
If the clock signal is not input, the crystal
oscillator (X200) and its peripheral chips may
be defective or improperly mounted. Resolder
them. If the problem is not resolved, replace
them.
If the clock signal is not input, the crystal
oscillator (X500) and its peripheral chips may
be defective or improperly mounted. Resolder
them. If the problem is not resolved, replace
them.
