Check item(3-5.4.). Check the SPI communication line :
Check the CPU.
Is the "SPI" waveform of the TP near the DSP [IC781] correct (like
the one shown in the diagram) when the power is turned on?
IC781
CN782:6pin DSP_ICS
CN782:5pin DSP_MISO
CN782:4pin DSP_MOSI
CN782:3pin DSP_CLK
Check item(3-5.5.). Check the SPI communication line :
Check DSP [IC781], CPU [IC751] patterns as well as soldering.
If there is no problem, go to the next step.
Check the SPI communication line.
DSP [IC781] is faulty.
Replace with a new device.
YES
*The diagram shows an example.
(Signal patterns vary depending on the
timing.)
Points for checking waveforms
- Crest value (3.3V normally)
- Signal change
- CLOCK frequency (about 6MHz)
Voltage scale：2.0V/div
Time scale：2us/div
NOYES
Recheck from check item (3.1.).
If it does not work, replace the PCB.
Before Servicing
This Unit
Electrical Mechanical Repair Information Updating
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