Check item(3-10.4.).
Check the communication line :
Check the CPU.
Is the waveform of the TP near the DIR [
U1040
] correct (like the one
shown in the diagram) when the power is turned on?
U1040
DIR_CE
DIR_DOUT
DIR_DIN
DIR_CLK
Check item(3-10.5.).
Check the communication line :
Check DIR [
U1040
], CPU [
U1018
] patterns as well as soldering.
If there is no problem, go to the next step.
Check the communication line.
DIR [
U1040
] is faulty.
Replace with a new device.
YES
*The diagram shows an example.
(Signal patterns vary depending on the tim-
ing.)
Points for checking waveforms
- Crest value (3.3V normally)
- Signal change
- CLOCK frequency (about 2MHz)
Voltage scale：2.0V/div
Time scale：2us/div
NO
YES
Recheck from
check item (3.1.).
If it does not work, replace the PCB.
Before Servicing
This Unit
Electrical
Mechanical
Repair Information
Updating
109
