We are trying to signal to the PGA450 from an external processor that it is time for it to take a distance measurement.
We can put a pulse on a GPIO pin and poll it during main, but our application requires a reading to be taken at a known time so it would be preferable to use an interrupt to initiate the reading by the PGA450. The GPIO pins do not seem to be able to generate interrupts but the LIN pin might. Figure 38 in the datasheet suggests that an edge on the LIN pin could generate an external interrupt EX0 on port 3.2 and Table 0.68 in the programmers guide also suggests this.
I have set the LIN_SCI to LIN mode, LIN_CTRL to RX and set EX0 in TCON but applying a pulse of 0 to 7.5V on the LIN pin does not cause an interrupt. I am not sure exactly what the thresholds are for this pin but with Vpwr set at 9V, I would have thought that 7.5V would be enough.
Any suggestions on getting LIN RX interrupt to work or alternative ways to generate an interrupt from an external pulse?