NX-220
44
TROUBLE SHOOTING
■
Descriptions of signal names
1) RST(RESET)
: ASIC reset signal
LOW
→
Reset
2) /BINT
: Battery fi nal voltage monitoring
LOW
→
Final voltage
3) PSW
: Power switch signal
HIGH
→
ON
4) /FRST
: FLASH reset signal
LOW
→
Reset
5) SBC
: Switch B control
HIGH
→
ON
6) /DRST
: DSP reset signal
LOW
→
Reset
Replacing TX-RX Unit
■
TX-RX unit Information
Model Name
Original TX-RX unit
Number
For Service TX-RX
unit Number
NX-220
X57-8040-10
X57-8040-11
■
Method of confi rming “Original TX-RX unit” and
“Service TX-RX unit”
The 0
Ω
resistor (R4) is mounted
on the “R4” silk print part of the
Service TX-RX unit (X57-8040-11).
X57-804
Component side
R4
●
The LCD displays control *1
The LCD does not function even if it is exchanged with the Display unit. *1
It is unlikely that the BGA parts are broken.
Points to be checked
Normal voltage
/LCDCS R667
3.3V
→
0V
→
3.3V
If the /LCDCS is 0V or 3.3V, the ASIC/FLASH/SRAM
may be broken.
When a normal
value is confirmed.
When an abnormal
value is confirmed.
●
When an error display appears on the LCD *1
The LCD displays “ERR 1”.
An error occurs when the ASIC internal RAM reads
or writes. The ASIC may be broken.
The LCD displays “ERR 2”.
An error occurs when the DSP internal RAM reads
or writes. The DSP may be broken.
The LCD displays “ERR 3”.
An error occurs when the SRAM internal RAM reads
or writes. The SRAM may be broken.
●
When the LED color changes red and orange alternately *2
*1: C model only
*2: C2 model only
A warning tone sounds
The frequency data was not written.
(Unprogramming)
A warning tone does not sound
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.
An error occurs when the SRAM internal RAM reads
or writes. The SRAM may be broken.
or
or