Check item(27).
Check the communication line :
Check the CPU.
Is the waveform of the TP near the DIR [
IC761
] correct (like the one
shown in the diagram) when the power is turned on?
IC761
DR_CK
DR_DOUT
DR_CE
DR_DIN
Check item(28).
Check the communication line :
Check DIR [
IC761
], CPU[
IC751
] patterns as well as soldering.
If there is no problem, go to the next step.
Check the communication line.
DIR [
IC761
] 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 2 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.
89
Caution in
servicing
Electrical
Mechanical
Repair Information
Updating
Summary of Contents for AVR-S730H
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