Hi,
BMA400 interrupts are in non-latched mode by default. This means that when the interrupt condition is true, interrupt will be generated. If the interrupt is mapped to INT1 pin or INT2 pin, then you will see a pulse on that pin. After a certain amount of time, the interrupt will be cleared by itself. The corresponding bit to the interrupt in INT_STATx registers is identital to interrupt signal on INT1 or INT2 pin. This means that when interrupt signal is cleared, the corresponding bit in INT_STATx will be cleared as well. If you are lucky enough you may read that bit from INT_STATx register with value of "1".
Data ready interrupt is described in BMA400 datasheet as shown below. If you want to get data ready interrupt bit with value of "1" from INT_STATx registers, then you can write value of 0x8C to register 0x20 in the sample pseudo code to latch the interrupt. After you read INT_STATx registers all the corresponding interrupt bits will be cleared.
If you want to read tap interrupt bits from INT_STATx registers, you can do the same thing by writing the value of 0x8C to register 0x20 to latch the interrupts.
Thanks.
... View more