machine
The machine module contains specific functions related to the hardware on a particular board. Most functions in this module allow to achieve direct and unrestricted access to and control of hardware blocks on a system (like CPU, timers, buses, etc.). Used incorrectly, this can lead to malfunction, lockups, crashes of your board, and in extreme cases, hardware damage.
A note of callbacks used by functions and class methods of machine module: all these callbacks should be considered as executing in an interrupt context. This is true for both physical devices with IDs >= 0 and "virtual" devices with negative IDs like -1 (these "virtual" devices are still thin shims on top of real hardware and real hardware interrupts). See isr_rules.
reset()
Resets the device in a manner similar to pushing the external RESET button.
soft_reset()
Performs a soft reset of the interpreter, deleting all Python objects and resetting the Python heap. It tries to retain the method by which the user is connected to the MicroPython REPL (eg serial, USB, Wifi).
reset_cause()
Get the reset cause. See constants <machine_constants> for the possible return values.
disable_irq()
Disable interrupt requests. Returns the previous IRQ state which should be considered an opaque value. This return value should be passed to the enable_irq() function to restore interrupts to their original state, before disable_irq() was called.
enable_irq(state)
Re-enable interrupt requests. The state parameter should be the value that was returned from the most recent call to the disable_irq() function.
freq()
Returns CPU frequency in hertz.
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).
sleep()
Note
This function is deprecated, use lightsleep() instead with no arguments.
lightsleep([time_ms]) deepsleep([time_ms])
Stops execution in an attempt to enter a low power state.
If time_ms is specified then this will be the maximum time in milliseconds that the sleep will last for. Otherwise the sleep can last indefinitely.
With or without a timout, execution may resume at any time if there are events that require processing. Such events, or wake sources, should be configured before sleeping, like Pin change or RTC timeout.
The precise behaviour and power-saving capabilities of lightsleep and deepsleep is highly dependent on the underlying hardware, but the general properties are:
- A lightsleep has full RAM and state retention. Upon wake execution is resumed from the point where the sleep was requested, with all subsystems operational.
- A deepsleep may not retain RAM or any other state of the system (for example peripherals or network interfaces). Upon wake execution is resumed from the main script, similar to a hard or power-on reset. The reset_cause() function will return machine.DEEPSLEEP and this can be used to distinguish a deepsleep wake from other resets.
wake_reason()
Get the wake reason. See constants <machine_constants> for the possible return values.
Availability: ESP32, WiPy.
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.
time_pulse_us(pin, pulse_level, timeout_us=1000000, /)
Time a pulse on the given pin, and return the duration of the pulse in microseconds. The pulse_level argument should be 0 to time a low pulse or 1 to time a high pulse.
If the current input value of the pin is different to pulse_level, the function first () waits until the pin input becomes equal topulse_level*, then (*) times the duration that the pin is equal topulse_level*. If the pin is already equal to pulse_level then timing starts straight away.
The function will return -2 if there was timeout waiting for condition marked () above, and -1 if there was timeout during the main measurement, marked () above. The timeout is the same for both cases and given bytimeout_us* (which is in microseconds).
rng()
Return a 24-bit software generated random number.
Availability: WiPy.
machine.IDLE machine.SLEEP machine.DEEPSLEEP
IRQ wake values.
machine.PWRON_RESET machine.HARD_RESET machine.WDT_RESET machine.DEEPSLEEP_RESET machine.SOFT_RESET
Reset causes.
machine.WLAN_WAKE machine.PIN_WAKE machine.RTC_WAKE
Wake-up reasons.
machine.Pin.rst machine.Signal.rst machine.ADC.rst machine.UART.rst machine.SPI.rst machine.I2C.rst machine.RTC.rst machine.Timer.rst machine.WDT.rst machine.SD.rst machine.SDCard.rst