Hi all,
My customer is faced with the key scan problem as follow;
When a key is pushed down about 10,000 times continuously, the interrupt doesn't occur any more suddenly,
and even if a key is pushed down after that, interrupt doesn't occur.
When a problem has occurred, a Low pulsed output of COLx of scan stops,
and the information which pushed down a key as a result doesn't seem readable.
After such phenomenon has occurred, TCA8418 normally returns by H/W RESET .
Can I have the advice to settle this phenomenon?
Dumped register data when problem occured.
address | read value |
00 | - |
01 | 19 |
02 | 0 |
03 | 0 |
04 | 0 |
05 | 0 |
06 | 0 |
07 | 0 |
08 | 0 |
09 | 0 |
0A | 0 |
0B | 0 |
0C | 0 |
0D | 0 |
0E | 0 |
0F | 0 |
10 | 0 |
11 | 0 |
12 | 0 |
13 | 0 |
14 | FF |
15 | FF |
16 | 3 |
17 | 0 |
18 | 0 |
19 | 0 |
1A | 0 |
1B | 0 |
1C | 0 |
1D | FF |
1E | 7F |
1F | 0 |
20 | 0 |
21 | 0 |
22 | 0 |
23 | 0 |
24 | 0 |
25 | 0 |
26 | 0 |
27 | 0 |
28 | 0 |
29 | FF |
2A | 7F |
2B | 0 |
2C | 0 |
2D | 0 |
2E | 0 |
2F | - |
COL3 output wave form:
Regards,
Toshi