4.3.7 Tamper Detection

The ATSAML22N18A supports up to five selectable external inputs and one output that can be used for tamper detection. When tamper is detected a time stamp is logged and an interrupt is raised. The output pin can be used for PCB active layer detection, when enabled a bit pattern is applied to the output pin, if this pattern is not received at an input pin a tamper is detected.

All tamper inputs and the output is connected to EXT1 and EXT2. Using a jumper between PB01 and an input can emulate for example the chassis of a product being opened or a modification to a PCB.

For more details about how the tamper functionality works, see the SAM L22 datasheet.

Table 4-18. Tamper Detection
SAM L22 pinTamper nameShared functionality
PC00IN[3]EXT2 pin 9, Shield, and EDBG GPIO2
PC01IN[4]EXT2 pin 10, Shield, User SW0, and EDBG GPIO3
PA02IN[2]EXT1 pin 3
PB00IN[0]EXT1 pin 16
PB01OUTEXT1 pin 18
PB02IN[1]EXT1 pin 17