Kenwood NX-411 Service Manual page 34

NX-411
● Checking the output signal
from the ASIC
Points to be checked
SBC R213
Points to be checked
/DRST IC309 side R324
● The LCD displays control
Points to be checked
/LCDRST IC309 side C326
Points to be checked
/CS4 IC302 (7 pin)
Points to be checked
5A IC204 (5 pin)
It is unlikely that the BGA parts are broken.
● When an error display appears on the LCD.
The LCD displays "INIT ERROR1".
The LCD displays "INIT ERROR2".
The LCD displays "INIT ERROR3".
*1: When writing firmware version earlier than version 2.80, this error display appears.
■ Descriptions of signal names
1) RST(RESET) : ASIC reset signal
2) /BINT : Battery fi nal voltage monitoring
3) /PSW : Power switch signal
4) /FRST : FLASH reset signal
5) SBC : Switch B control
6) /DRST : DSP reset signal
7) /LCDRST : LCD reset signal
8) /CS4 : LCD controller chip select signal
9) 5A : Analog peripheral control 5.0V power supply
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TROUBLE SHOOTING
When a normal
value is confirmed.
When an abnormal
value is confirmed.
Normal voltage
3.3V
When a normal
value is confirmed.
When an abnormal
value is confirmed.
Normal voltage
3.3V
When a normal
value is confirmed.
When an abnormal
value is confirmed.
Normal voltage
3.3V
When a normal
value is confirmed.
When an abnormal
value is confirmed.
Normal voltage
3.3V→0V→3.3V
When a normal
value is confirmed.
When an abnormal
value is confirmed.
Normal voltage
5.0V
When a normal
value is confirmed.
LOW Reset
LOW Final voltage
LOW ON
LOW Reset
HIGH ON
LOW Reset
LOW Reset
LOW Active
Remove R213. If the ASIC side is 0V,
the ASIC/FLASH/SRAM may be broken.
If the /DRST is 0V, the ASIC/FLASH/SRAM are broken.
If the /LCDRST is 0V,
the ASIC/FLASH/SRAM may be broken.
If the /CS4 is 0V or 3.3V, the ASIC/FLASH/SRAM
may be broken.
If 5A is 0V, parts other than the BGA are broken.
An error occurs when the ASIC internal RAM reads
or writes. The ASIC may be broken.
An error occurs when the DSP internal RAM reads
or writes. The DSP may be broken. *1
An error occurs when the SRAM internal RAM
reads or writes. The SRAM may be broken.