Machine

The machine module contains specific functions related to the board.

Quick Usage Example

Reset Functions

machine.reset()

Resets the device in a manner similar to pushing the external RESET button.

machine.reset_cause()

Returns an integer. The possible values are:

• machine.PWRON_RESET: Reset by power on or reset button
• machine.HARD_RESET:
• machine.WDT_RESET: Reset by watchdog timer
• machine.DEEPSLEEP_RESET: Reset caused by deep sleep
• machine.SOFT_RESET: Reset by e.g. sys.init()
• machine.BROWN_OUT_RESET: Reset caused by low voltage

Interrupt Functions

machine.disable_irq()

Disable interrupt requests. Returns and integer representing the previous IRQ state. This return value can be passed to enable_irq to restore the IRQ to its original state.

machine.enable_irq(state)

Enable interrupt requests. The most common use of this function is to pass the value returned by disable_irq to exit a critical section. Another options is to enable all interrupts which can be achieved by calling the function with no parameters.

Power Functions

machine.freq()

Returns CPU frequency in hertz.

machine.idle()

Gates the clock to the CPU, useful to reduce power consumption at any time during short or long periods. Peripherals continue working and execution resumes as soon as any interrupt is triggered (on many ports this includes system timer interrupt occurring at regular intervals on the order of millisecond).

machine.sleep([time_ms, resume_wifi_ble=False])

Sets the device in to light sleep mode , where in this mode digital peripherals, most of the RAM, and CPUs are clock-gated, and supply voltage is reduced. Upon exit from light sleep, peripherals and CPUs resume operation, their internal state is preserved.

• time_ms is the sleep time in milliseconds. If not given, it will sleep indefinitely unless power is removed, the reset button is pressed or another wakeup source is configured.
• resume_wifi_ble is a boolean value that enables or disable restoring after wakeup any WiFi or BLE connection that was interrupted by light sleep.
  • True Restore WiFi / BLE connections
  • False Do not restore WiFi / BLE connections restoration (default)

machine.deepsleep([time_ms])

Stops the CPU and all peripherals, including the networking interfaces (except for LTE). Execution is resumed similar to pressing the reset button. The pin states are not held by default. You can choose to hold specific pins using machine.pin.hold()

• time_ms is the sleep time in milliseconds. If not given, it will sleep indefinitely unless power is removed, the reset button is pressed or another wakeup source is configured.

Products with LTE connectivity, such as the FiPy, GPy, G01, need to have the LTE radio disabled separately via the LTE class before entering deep sleep. This is necessary because the LTE radio is powered independently, which allows for use cases that wake the system from deep sleep by an event from the LTE network, for example receiving data or an SMS.

machine.pin_sleep_wakeup(pins, mode, enable_pull)

Configure pins to wake up from sleep mode. The pins which have this capability are: P2, P3, P4, P6, P8 to P10 and P13 to P23.

The arguments are:

• pins a list or tuple containing the GPIO to setup for sleep wakeup.
• mode selects the way the configure GPIOs can wake up the module. The possible values are:
  • machine.WAKEUP_ALL_LOW
  • machine.WAKEUP_ANY_HIGH.
• enable_pull if set to True keeps the pull up or pull down resistors enabled during sleep. If this variable is set to True, then ULP or capacitive touch wakeup cannot be used in combination with GPIO wakeup.

machine.wake_reason()

Get the wake reason. See constants for the possible return values. Returns a tuple of the form: (wake_reason, gpio_list). When the wakeup reason is either GPIO or touch pad, then the second element of the tuple is a list with GPIOs that generated the wakeup. The possible wake reasons are:

• machine.PWRON_WAKE: Wake up by power on or reset button
• machine.PIN_WAKE: Wake up by interrupt on pin
• machine.RTC_WAKE: Wake up because sleep time is over
• machine.ULP_WAKE: Wake up by touch button

machine.remaining_sleep_time()

Returns the remaining timer duration (in milliseconds) if the ESP32 is woken up from deep sleep by something other than the timer. For example, if you set the timer for 30 seconds (30000 ms) and it wakes up after 10 seconds then this function will return 20000.

Miscellaneous Functions

machine.main(filename)

Set the filename of the main script to run after boot.py is finished. If this function is not called then the default file main.py will be executed.

It only makes sense to call this function from within boot.py.

machine.rng()

Return a 24-bit software generated random number.

machine.unique_id()

Returns a byte string with a unique identifier of a board/SoC. It will vary from a board/SoC instance to another, if underlying hardware allows. Length varies by hardware (so use substring of a full value if you expect a short ID). In some MicroPython ports, ID corresponds to the network MAC address.

machine.info()

Returns the high water mark of the stack associated with various system tasks, in words (1 word = 4 bytes on the ESP32). If the value is zero then the task has likely overflowed its stack.

machine.temperature()

Returns the temperature of the ESP32 core in degrees Fahrenheit. You can convert this to Celsius by ((machine.temperature() - 32) / 1.8)

Constants

Reset Causes

machine.PWRON_RESET, machine.HARD_RESET, machine.WDT_RESET, machine.DEEPSLEEP_RESET, machine.SOFT_RESET, machine.BROWN_OUT_RESET

Wake Reasons

machine.PWRON_WAKE, machine.PIN_WAKE, machine.RTC_WAKE, machine.ULP_WAKE

Pin Wakeup Modes

machine.WAKEUP_ALL_LOW, machine.WAKEUP_ANY_HIGH