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Updated FAQ (markdown)

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tmk 2014-03-24 17:01:43 -07:00
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@ -88,3 +88,22 @@ Use `1UL<<16` intead of `1<<16` in `read_cols()` in **matrix.h** when your colum
In C `1` means one of **int** type which is **16bit** in case of AVR so you can't shift left more than 15. You will get unexpected zero when you say `1<<16`. You have to use **unsigned long** type with `1UL`.
http://deskthority.net/workshop-f7/rebuilding-and-redesigning-a-classic-thinkpad-keyboard-t6181-60.html#p146279
## Pull-up Resistor
In some case converters needed to have pull-up resistors to work correctly. Place the resistor between VCC and signal line in parallel.
```
Keyboard Conveter
,------.
5V------+------|VCC |
| | |
R | |
| | |
Signal--+------|PD0 |
| |
GND------------|GND |
`------'
R: 1K Ohm resistor
```