I'm evaluating nF51822 for my application which needs to wake up from either a button press or an interrupt pin singal from an accelerometer. Normally this can be done with enabling GPIO interrupt while putting the CPU to sleep, but from nRF51 manual it seems the GPIO "pin sensing" feature won't generate an interrupt like traditional MCUs (correct?); GPIOTE is needed to generate such an event as done in app_button.c
And a discussion here says a hardware issue that can cause ~1mA in sleep mode if GPIOTE is enabled. devzone.nordicsemi.com/.../power-use-with-gpiote-is-too-high
This worries me... I can't affort such a sleeping current. Could someone kindly show me a way around this issue? BTW, SoftDevice is needed.
@Nordic: if I still want to use nRF51 for a project that plans to go MP in the next 6 month, can I expect the issue will be fixed by then?
It's only the CONFIG channels in GPIOTE that will cause high current consumption, and the chip can always be woken up by using the PORT event instead of the CONFIG channels. This means that it's perfectly…
I thought for a while... maybe an external solution is possible? But can the chip be waken up from an external source without involving GPIOTE?
For example, how about (mis)using the CTS/RTS pins to fake a successful TX/RX and use one of the EVENTS generated? Leaving the UART running still needs ~0.2mA, though.
Better ideas?