13SPECTRA: RTC alarm INT is on GPIO2, not GPIO18

TECHNICAL SUPPORT Inkplate
1

On my 13SPECTRA, the Inkplate13SPECTRA_RTC_Alarm_With_Deep_Sleep example never wakes on its alarm: it arms GPIO18 (“RTC interrupt for alarm connected to GPIO18”), but on
this board the PCF85063A’s INT is wired to GPIO2. GPIO18 appears to be only the WAKE button.

What I observed (library 11.1.2, alarm set via
rtc.setAlarmEpoch(rtc.getEpoch() + 60, RTC_ALARM_MATCH_DHHMMSS)):

  • The alarm itself works: AF sets after exactly 60s, CTRL_2 reads 0xC0
    (AIE | AF). But GPIO18 stays high, even fully awake with the flag asserted,
    and deep sleep armed on GPIO18 sleeps through the alarm.
  • Diffing all RTC-capable GPIOs across the AF edge: GPIO2 drops the moment
    AF sets     and stays low until the flag clears (level INT - not CLKOUT, which
    would toggle, and JP2 is open anyway).
  • Deep sleep with esp_sleep_enable_ext0_wakeup(GPIO_NUM_2, 0) wakes on the
    alarm second.

My fix, working reliably since:

esp_sleep_enable_ext0_wakeup(GPIO_NUM_18, 0);  // WAKE button
esp_sleep_enable_ext1_wakeup(1ULL << 2, ESP_EXT1_WAKEUP_ANY_LOW);  // RTC INT

I’d suggest you fix the example and RTC docs to use GPIO2 and document the INT
routing on the hardware/jumpers page (it currently only mentions IO2 as the
optional JP2 clock output).

2

Hello jhurstus,
Thank you for bringing this to our attention, indeed the example seems to use the wrong IO pin for the RTC interrupt. We will change said example and publish a new release with it this week.