Check item(22).
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
D_CK
D_MOSI
D_CS
D_MISO
Check item(23).
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 (3.3 V normally)
- Signal change
- CLOCK frequency (about 6 MHz)
Voltage scale：2.0V/div
Time scale：2us/div
NO
YES
Recheck from
check item (1).
If it does not work, replace the PCB.
87
Caution in
servicing
Electrical
Mechanical
Repair Information
Updating
Summary of Contents for AVR-S730H
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