Hi @SHala.2 ,
Welcome to ST Community!
In order to route INT2 pin on INT1 pin you need to turn on the accelerometer in CTRL1 (reg 20h), then to drive the signal on the INT2 pin you need to set the corresponding interrupt bit of the CTRL5_INT2_PAD_CTRL register to 1. To route the INT2 pin signals on the INT1 pin set bit INT2_ON_INT1 = 1 in register CTRL7. This works only for the first 5 interrupts, the last three can be set directly through register CTRL4_INT1_PAD_CTRL. Finally, setting the INTERRUPTS_ENABLE bit in register CTRL7 to '1' you enable the interrupts.
If following these steps it doesn't work, you could set also the BDU (block data update) bit to 1 in the CTRL2 (21h) register.
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