# Information Gathering

## Detect UART Pin

### Check the board

some hardware mark the UART pin (if we super lucky).

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### Use Multimeter

#### Ground

set multimeter to continuity mode, `short` the multimeter to hear the Beeb.

Put the ground (multimeter) to the plat or any ground on the device. \
Then test any pin. If you hear the Beeb, it mean that is the ground.

#### VCC

set multimeter to 20V, then put the ground (multimeter) on the ground device.\
and test the others pin.

If its return 3.3 V constantly It mean VCC.

If it always changing the volt it mean **RX**

If it constant volt, it mean **TX**.