micropython · cwalther · Jan 5, 2024 · Jan 5, 2024
diff --git a/docs/library/machine.Pin.rst b/docs/library/machine.Pin.rst
@@ -42,7 +42,7 @@ Usage Model::
 Constructors
 ------------
 
-.. class:: Pin(id, mode=-1, pull=-1, *, value=None, drive=0, alt=-1)
+.. class:: Pin(id, mode=-1, pull=-1, *, value=None, drive=0, alt=-1, sense=-1)
 
    Access the pin peripheral (GPIO pin) associated with the given ``id``.  If
    additional arguments are given in the constructor then they are used to initialise
@@ -97,6 +97,15 @@ Constructors
        one pin alternate function is supported the this argument is not required.  Not all
        ports implement this argument.
 
+     - ``sense`` specifies whether and on what input value the pin contributes to the
+       *DETECT* signal, which wakes an nRF51/52 system from deep sleep. It can be one of:
+
+       - ``Pin.SENSE_DISABLED`` - Do not wake from this pin.
+       - ``Pin.SENSE_LOW`` - Wake when pin is low.
+       - ``Pin.SENSE_HIGH`` - Wake when pin is high.
+
+       Availability: nrf port.
+
    As specified above, the Pin class allows to set an alternate function for a particular
    pin, but it does not specify any further operations on such a pin.  Pins configured in
    alternate-function mode are usually not used as GPIO but are instead driven by other
@@ -108,7 +117,7 @@ Constructors
 Methods
 -------
 
-.. method:: Pin.init(mode=-1, pull=-1, *, value=None, drive=0, alt=-1)
+.. method:: Pin.init(mode=-1, pull=-1, *, value=None, drive=0, alt=-1, sense=-1)
 
    Re-initialise the pin using the given parameters.  Only those arguments that
    are specified will be set.  The rest of the pin peripheral state will remain
@@ -274,3 +283,13 @@ not all constants are available on all ports.
           Pin.IRQ_HIGH_LEVEL
 
    Selects the IRQ trigger type.
+
+.. data:: Pin.SENSE_DISABLED
+          Pin.SENSE_LOW
+          Pin.SENSE_HIGH
+
+   Selects the *SENSE* configuration of the pin, which determines
+   whether and on what input value it contributes to the *DETECT*
+   signal, which wakes the system from deep sleep.
+
+   Availability: nrf port.
diff --git a/docs/library/machine.rst b/docs/library/machine.rst
@@ -160,6 +160,15 @@ Power related functions
      return `machine.DEEPSLEEP` and this can be used to distinguish a deepsleep wake
      from other resets.
 
+   *nrf port:*
+
+   * The *time_ms* argument to `deepsleep` is ignored, the sleep is always indefinite.
+     nRF microcontrollers are incapable of waking on a timer as all clocks are off in
+     the deep sleep state.
+
+   * Pins are configured as wake sources using the ``sense`` argument to the
+     `Pin` constructor.
+
 .. function:: wake_reason()
 
    Get the wake reason. See :ref:`constants <machine_constants>` for the possible return values.

diff --git a/ports/nrf/modules/machine/modmachine.c b/ports/nrf/modules/machine/modmachine.c
@@ -49,12 +49,20 @@
 #if MICROPY_PY_MACHINE_RTCOUNTER
 #include "rtcounter.h"
 #endif
+#if defined(POWER_SYSTEMOFF_SYSTEMOFF_Enter)
+// nRF51/52
+#include "nrf_power.h"
+#elif defined(REGULATORS_SYSTEMOFF_SYSTEMOFF_Enable)
+// nRF91
+#include "nrf_regulators.h"
+#endif
 
+#define PYB_RESET_POWER_ON  (32)
 #define PYB_RESET_HARD      (0)
 #define PYB_RESET_WDT       (1)
 #define PYB_RESET_SOFT      (2)
 #define PYB_RESET_LOCKUP    (3)
-#define PYB_RESET_POWER_ON  (16)
+#define PYB_RESET_DEEPSLEEP (16)
 #define PYB_RESET_LPCOMP    (17)
 #define PYB_RESET_DIF       (18)
 #define PYB_RESET_NFC       (19)
@@ -93,11 +101,12 @@
     MICROPY_PY_MACHINE_RTCOUNTER_ENTRY \
     MICROPY_PY_MACHINE_TIMER_ENTRY \
     MICROPY_PY_MACHINE_TEMP_ENTRY \
+    { MP_ROM_QSTR(MP_QSTR_PWRON_RESET),        MP_ROM_INT(PYB_RESET_POWER_ON) }, \
     { MP_ROM_QSTR(MP_QSTR_HARD_RESET),         MP_ROM_INT(PYB_RESET_HARD) }, \
     { MP_ROM_QSTR(MP_QSTR_WDT_RESET),          MP_ROM_INT(PYB_RESET_WDT) }, \
     { MP_ROM_QSTR(MP_QSTR_SOFT_RESET),         MP_ROM_INT(PYB_RESET_SOFT) }, \
     { MP_ROM_QSTR(MP_QSTR_LOCKUP_RESET),       MP_ROM_INT(PYB_RESET_LOCKUP) }, \
-    { MP_ROM_QSTR(MP_QSTR_PWRON_RESET),        MP_ROM_INT(PYB_RESET_POWER_ON) }, \
+    { MP_ROM_QSTR(MP_QSTR_DEEPSLEEP_RESET),    MP_ROM_INT(PYB_RESET_DEEPSLEEP) }, \
     { MP_ROM_QSTR(MP_QSTR_LPCOMP_RESET),       MP_ROM_INT(PYB_RESET_LPCOMP) }, \
     { MP_ROM_QSTR(MP_QSTR_DEBUG_IF_RESET),     MP_ROM_INT(PYB_RESET_DIF) }, \
     MICROPY_PY_MACHINE_NFC_RESET_ENTRY \
@@ -115,7 +124,7 @@ void machine_init(void) {
     } else if (state & POWER_RESETREAS_LOCKUP_Msk) {
         reset_cause = PYB_RESET_LOCKUP;
     } else if (state & POWER_RESETREAS_OFF_Msk) {
-        reset_cause = PYB_RESET_POWER_ON;
+        reset_cause = PYB_RESET_DEEPSLEEP;
     #if !defined(NRF9160_XXAA)
     } else if (state & POWER_RESETREAS_LPCOMP_Msk) {
         reset_cause = PYB_RESET_LPCOMP;
@@ -126,10 +135,12 @@ void machine_init(void) {
     } else if (state & POWER_RESETREAS_NFC_Msk) {
         reset_cause = PYB_RESET_NFC;
     #endif
+    } else {
+        reset_cause = PYB_RESET_POWER_ON;
     }
 
     // clear reset reason
-    NRF_POWER->RESETREAS = (1 << reset_cause);
+    NRF_POWER->RESETREAS = 0xFFFFFFFF;
 }
 
 // machine.info([dump_alloc_table])
@@ -200,7 +211,18 @@ static void mp_machine_lightsleep(size_t n_args, const mp_obj_t *args) {
 }
 
 NORETURN static void mp_machine_deepsleep(size_t n_args, const mp_obj_t *args) {
-    mp_machine_reset();
+    #if defined(POWER_SYSTEMOFF_SYSTEMOFF_Enter)
+    // nRF51/52
+    nrf_power_system_off(NRF_POWER);
+    #elif defined(REGULATORS_SYSTEMOFF_SYSTEMOFF_Enable)
+    // nRF91
+    nrf_regulators_system_off(NRF_REGULATORS);
+    #else
+    #error figure out how to enter System OFF mode on this chip
+    #endif
+    // never reached, just to convince the compiler of NORETURN
+    for (;;) {
+    }
 }
 
 static mp_int_t mp_machine_reset_cause(void) {

diff --git a/ports/nrf/modules/machine/pin.c b/ports/nrf/modules/machine/pin.c
@@ -349,6 +349,7 @@ static mp_obj_t pin_obj_init_helper(const pin_obj_t *self, mp_uint_t n_args, con
         { MP_QSTR_af, MP_ARG_INT, {.u_int = -1}}, // legacy
         { MP_QSTR_value, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL}},
         { MP_QSTR_alt, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = -1}},
+        { MP_QSTR_sense, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = -1}},
     };
 
     // parse args
@@ -374,13 +375,21 @@ static mp_obj_t pin_obj_init_helper(const pin_obj_t *self, mp_uint_t n_args, con
     nrf_gpio_pin_input_t input = (mode == NRF_GPIO_PIN_DIR_INPUT) ? NRF_GPIO_PIN_INPUT_CONNECT
                                                                   : NRF_GPIO_PIN_INPUT_DISCONNECT;
 
+    // sense mode (default unmodified)
+    nrf_gpio_pin_sense_t sense = (nrf_gpio_pin_sense_t)args[5].u_int;
+    if (sense == (nrf_gpio_pin_sense_t)-1) {
+        sense = nrf_gpio_pin_sense_get(self->pin);
+    } else if (sense != NRF_GPIO_PIN_NOSENSE && sense != NRF_GPIO_PIN_SENSE_LOW && sense != NRF_GPIO_PIN_SENSE_HIGH) {
+        mp_raise_msg_varg(&mp_type_ValueError, MP_ERROR_TEXT("invalid pin sense: %d"), sense);
+    }
+
     if (mode == NRF_GPIO_PIN_DIR_OUTPUT || mode == NRF_GPIO_PIN_DIR_INPUT) {
         nrf_gpio_cfg(self->pin,
             mode,
             input,
             pull,
             NRF_GPIO_PIN_S0S1,
-            NRF_GPIO_PIN_NOSENSE);
+            sense);
     } else {
         mp_raise_msg_varg(&mp_type_ValueError, MP_ERROR_TEXT("invalid pin mode: %d"), mode);
     }
@@ -614,6 +623,10 @@ static const mp_rom_map_elem_t pin_locals_dict_table[] = {
     { MP_ROM_QSTR(MP_QSTR_AF_OD),     MP_ROM_INT(GPIO_MODE_AF_OD) },
     { MP_ROM_QSTR(MP_QSTR_PULL_NONE), MP_ROM_INT(GPIO_NOPULL) },
 */
+    { MP_ROM_QSTR(MP_QSTR_SENSE_DISABLED), MP_ROM_INT(NRF_GPIO_PIN_NOSENSE) },
+    { MP_ROM_QSTR(MP_QSTR_SENSE_LOW),      MP_ROM_INT(NRF_GPIO_PIN_SENSE_LOW) },
+    { MP_ROM_QSTR(MP_QSTR_SENSE_HIGH),     MP_ROM_INT(NRF_GPIO_PIN_SENSE_HIGH) },
+
     #include "genhdr/pins_af_const.h"
 };