MicroPython documentation and references

• Quick reference for the pyboard
  • General board control
  • Delay and timing
  • Internal LEDs
  • Internal switch
  • Pins and GPIO
  • Servo control
  • External interrupts
  • Timers
  • RTC (real time clock)
  • PWM (pulse width modulation)
  • ADC (analog to digital conversion)
  • DAC (digital to analog conversion)
  • UART (serial bus)
  • SPI bus
  • I2C bus
  • CAN bus (controller area network)
  • Internal accelerometer
• General information about the pyboard
  • Local filesystem and SD card
  • Boot modes
  • Errors: flashing LEDs
  • Guide for using the pyboard with Windows
  • The pyboard hardware
  • Datasheets for the components on the pyboard
  • Datasheets for other components
• MicroPython tutorial for the pyboard
  • 1. Introduction to the pyboard
    • 1.1. Caring for your pyboard
    • 1.2. Layout of the pyboard
    • 1.3. Plugging in and powering on
    • 1.4. Powering by an external power source
  • 2. Running your first script
    • 2.1. Connecting your pyboard
    • 2.2. Opening the pyboard USB drive
    • 2.3. Editing main.py
    • 2.4. Resetting the pyboard
  • 3. Getting a MicroPython REPL prompt
    • 3.1. Windows
    • 3.2. Mac OS X
    • 3.3. Linux
    • 3.4. Using the REPL prompt
    • 3.5. Resetting the board
  • 4. Turning on LEDs and basic Python concepts
    • 4.1. A Disco on your pyboard
    • 4.2. The Special LEDs
  • 5. The Switch, callbacks and interrupts
    • 5.1. Switch callbacks
    • 5.2. Technical details of interrupts
    • 5.3. Further reading
  • 6. The accelerometer
    • 6.1. Using the accelerometer
    • 6.2. Making a spirit level
  • 7. Safe mode and factory reset
    • 7.1. Safe mode
    • 7.2. Factory reset the filesystem
  • 8. Making the pyboard act as a USB mouse
    • 8.1. Sending mouse events by hand
    • 8.2. Making a mouse with the accelerometer
    • 8.3. Restoring your pyboard to normal
  • 9. The Timers
    • 9.1. Timer counter
    • 9.2. Timer callbacks
    • 9.3. Making a microsecond counter
  • 10. Inline assembler
    • 10.1. Returning a value
    • 10.2. Accessing peripherals
    • 10.3. Accepting arguments
    • 10.4. Loops
    • 10.5. Further reading
  • 11. Power control
  • Tutorials requiring extra components
    • 1. Controlling hobby servo motors
      • 1.1. Creating a Servo object
      • 1.2. Continuous rotation servos
      • 1.3. Calibration
    • 2. Fading LEDs
      • 2.1. Components
      • 2.2. Connecting Things Up
      • 2.3. Code
      • 2.4. Breathing Effect
      • 2.5. Advanced Exercise
      • 2.6. Addendum
    • 3. The LCD and touch-sensor skin
      • 3.1. Using the LCD
      • 3.2. Using the touch sensor
    • 4. The AMP audio skin
      • 4.1. Example code
    • 5. The LCD160CR skin
      • 5.1. Plugging in the display
      • 5.2. Getting the driver
      • 5.3. Testing the display
      • 5.4. Drawing some graphics
      • 5.5. Using the touch sensor
      • 5.6. Directing the MicroPython output to the display
  • Tips, tricks and useful things to know
    • 1. Debouncing a pin input
    • 2. Making a UART - USB pass through
• MicroPython libraries
  • Python standard libraries and micro-libraries
    • Builtin functions and exceptions
      • Functions and types
      • Exceptions
    • array – arrays of numeric data
      • Classes
    • cmath – mathematical functions for complex numbers
      • Functions
      • Constants
    • gc – control the garbage collector
      • Functions
    • math – mathematical functions
      • Functions
      • Constants
    • sys – system specific functions
      • Functions
      • Constants
    • ubinascii – binary/ASCII conversions
      • Functions
    • ucollections – collection and container types
      • Classes
    • uerrno – system error codes
      • Constants
    • uhashlib – hashing algorithms
      • Constructors
      • Methods
    • uheapq – heap queue algorithm
      • Functions
    • uio – input/output streams
      • Conceptual hierarchy
      • Functions
      • Classes
    • ujson – JSON encoding and decoding
      • Functions
    • uos – basic “operating system” services
      • Functions
    • ure – simple regular expressions
      • Functions
      • Regex objects
      • Match objects
    • uselect – wait for events on a set of streams
      • Functions
      • class Poll
        • Methods
    • usocket – socket module
      • Socket address format(s)
      • Functions
      • Constants
        • class socket
      • Methods
    • ustruct – pack and unpack primitive data types
      • Functions
    • utime – time related functions
      • Functions
    • uzlib – zlib decompression
      • Functions
  • MicroPython-specific libraries
    • btree – simple BTree database
      • Functions
      • Methods
      • Constants
    • framebuf — Frame buffer manipulation
      • class FrameBuffer
      • Constructors
      • Drawing primitive shapes
      • Drawing text
      • Other methods
      • Constants
    • machine — functions related to the hardware
      • Reset related functions
      • Interrupt related functions
      • Power related functions
      • Miscellaneous functions
      • Constants
      • Classes
        • class Pin – control I/O pins
          • Constructors
          • Methods
          • Constants
        • class Signal – control and sense external I/O devices
          • Constructors
          • Methods
        • class UART – duplex serial communication bus
          • Constructors
          • Methods
        • class SPI – a Serial Peripheral Interface bus protocol (master side)
          • Constructors
          • Methods
          • Constants
        • class I2C – a two-wire serial protocol
          • Constructors
          • General Methods
          • Primitive I2C operations
          • Standard bus operations
          • Memory operations
        • class RTC – real time clock
          • Constructors
          • Methods
          • Constants
        • class Timer – control hardware timers
          • Constructors
          • Methods
          • Constants
        • class WDT – watchdog timer
          • Constructors
          • Methods
    • micropython – access and control MicroPython internals
      • Functions
    • network — network configuration
      • Common network adapter interface
      • class CC3K
        • Constructors
        • Methods
        • Constants
      • class WIZNET5K
        • Constructors
        • Methods
    • uctypes – access binary data in a structured way
      • Defining structure layout
      • Module contents
      • Structure descriptors and instantiating structure objects
      • Structure objects
      • Limitations
  • Libraries specific to the pyboard
    • pyb — functions related to the board
      • Time related functions
      • Reset related functions
      • Interrupt related functions
      • Power related functions
      • Miscellaneous functions
      • Classes
        • class Accel – accelerometer control
          • Constructors
          • Methods
          • Hardware Note
        • class ADC – analog to digital conversion
          • Constructors
          • Methods
          • The ADCAll Object
        • class CAN – controller area network communication bus
          • Constructors
          • Class Methods
          • Methods
          • Constants
        • class DAC – digital to analog conversion
          • Constructors
          • Methods
        • class ExtInt – configure I/O pins to interrupt on external events
          • Constructors
          • Class methods
          • Methods
          • Constants
        • class I2C – a two-wire serial protocol
          • Constructors
          • Methods
          • Constants
        • class LCD – LCD control for the LCD touch-sensor pyskin
          • Constructors
          • Methods
        • class LED – LED object
          • Constructors
          • Methods
        • class Pin – control I/O pins
          • Constructors
          • Class methods
          • Methods
          • Constants
        • class PinAF – Pin Alternate Functions
          • Methods
        • class RTC – real time clock
          • Constructors
          • Methods
        • class Servo – 3-wire hobby servo driver
          • Constructors
          • Methods
        • class SPI – a master-driven serial protocol
          • Constructors
          • Methods
          • Constants
        • class Switch – switch object
          • Constructors
          • Methods
        • class Timer – control internal timers
          • Constructors
          • Methods
        • class TimerChannel — setup a channel for a timer
          • Methods
        • class UART – duplex serial communication bus
          • Constructors
          • Methods
          • Constants
          • Flow Control
            • CTS: target controls Pyboard transmitter
            • RTS: Pyboard controls target’s transmitter
        • class USB_HID – USB Human Interface Device (HID)
          • Constructors
          • Methods
        • class USB_VCP – USB virtual comm port
          • Constructors
          • Methods
    • lcd160cr — control of LCD160CR display
      • class LCD160CR
      • Constructors
      • Static methods
      • Instance members
      • Setup commands
      • Pixel access methods
      • Drawing text
      • Drawing primitive shapes
      • Touch screen methods
      • Advanced commands
      • Constants
• The MicroPython language
  • Glossary
  • The MicroPython Interactive Interpreter Mode (aka REPL)
    • Auto-indent
    • Auto-completion
    • Interrupting a running program
    • Paste Mode
    • Soft Reset
    • The special variable _ (underscore)
    • Raw Mode
  • Writing interrupt handlers
    • Tips and recommended practices
    • MicroPython Issues
      • The emergency exception buffer
      • Simplicity
      • Communication between an ISR and the main program
      • The use of object methods as callbacks
      • Creation of Python objects
      • Use of Python objects
      • Overcoming the float limitation
      • Using micropython.schedule
    • Exceptions
    • General Issues
      • Interrupt Handler Design
      • Reentrancy
      • Critical Sections
      • Interrupts and the REPL
  • Maximising MicroPython Speed
    • Designing for speed
      • Algorithms
      • RAM Allocation
      • Buffers
      • Floating Point
      • Arrays
    • Identifying the slowest section of code
    • MicroPython code improvements
      • The const() declaration
      • Caching object references
      • Controlling garbage collection
    • The Native code emitter
    • The Viper code emitter
    • Accessing hardware directly
  • MicroPython on Microcontrollers
    • Flash Memory
    • RAM
      • Compilation Phase
      • Execution Phase
    • The Heap
      • Fragmentation
      • Reporting
      • Control of Garbage Collection
    • String Operations
    • Postscript
      • Footnote: gc.collect() return value
  • Inline Assembler for Thumb2 architectures
    • Document conventions
    • Instruction Categories
      • 1. Register move instructions
        • 1.1. Document conventions
        • 1.2. Register moves
      • 2. Load register from memory
        • 2.1. Document conventions
        • 2.2. Register Load
      • 3. Store register to memory
        • 3.1. Document conventions
        • 3.2. Register Store
      • 4. Logical & Bitwise instructions
        • 4.1. Document conventions
        • 4.2. Logical instructions
        • 4.3. Shift and rotation instructions
        • 4.4. Special instructions
      • 5. Arithmetic instructions
        • 5.1. Document conventions
        • 5.2. Addition
        • 5.3. Subtraction
        • 5.4. Negation
        • 5.5. Multiplication and division
      • 6. Comparison instructions
        • 6.1. Document conventions
        • 6.2. The Application Program Status Register (APSR)
        • 6.3. APSR Bits
        • 6.4. Comparison instructions
        • 6.5. Conditional execution
      • 7. Branch instructions
        • 7.1. Document conventions
        • 7.2. Branch to label
        • 7.3. Long branches
        • 7.4. Subroutines (functions)
      • 8. Stack push and pop
        • 8.1. Document conventions
        • 8.2. Stack operations
      • 9. Miscellaneous instructions
      • 10. Floating Point instructions
        • 10.1. Document conventions
        • 10.2. Arithmetic
        • 10.3. Move between ARM core and FPU registers
        • 10.4. Move between FPU register and memory
        • 10.5. Data Comparison
        • 10.6. Convert between integer and float
      • 11. Assembler Directives
        • 11.1. Labels
        • 11.2. Defining inline data
    • Usage examples
      • 1. Hints and tips
        • 1.1. Code branches and subroutines
        • 1.2. Argument passing and return
          • 1.2.1. Multiple arguments
          • 1.2.2. Non-integer data types
        • 1.3. Named constants
        • 1.4. Assembler code as class methods
        • 1.5. Use of unsupported instructions
        • 1.6. Overcoming MicroPython’s integer restriction
    • References
• MicroPython differences from CPython
  • Syntax
    • Spaces
      • uPy requires spaces between literal numbers and keywords, CPy doesn’t
    • Unicode
      • Unicode name escapes are not implemented
  • Core Language
    • Classes
      • Special method __del__ not implemented for user-defined classes
      • Method Resolution Order (MRO) is not compliant with CPython
      • When inheriting from multiple classes super() only calls one class
      • Calling super() getter property in subclass will return a property object, not the value
    • Functions
      • Error messages for methods may display unexpected argument counts
      • Unpacking function arguments in non-last position isn’t detected as an error
      • User-defined attributes for functions are not supported
    • Generator
      • Context manager __exit__() not called in a generator which does not run to completion
    • Runtime
      • Local variables aren’t included in locals() result
      • Code running in eval() function doesn’t have access to local variables
    • import
      • __path__ attribute of a package has a different type (single string instead of list of strings) in MicroPython
      • Failed to load modules are still registered as loaded
      • MicroPython does’t support namespace packages split across filesystem.
  • Builtin Types
    • Exception
      • Exception chaining not implemented
      • User-defined attributes for builtin exceptions are not supported
      • Exception in while loop condition may have unexpected line number
      • Exception.__init__ raises TypeError if overridden and called by subclass
    • bytearray
      • Array slice assignment with unsupported RHS
    • bytes
      • bytes() with keywords not implemented
      • Bytes subscription with step != 1 not implemented
    • float
      • uPy and CPython outputs formats may differ
    • int
      • No int conversion for int-derived types available
      • Incorrect error message when passing float into to_bytes
    • list
      • List delete with step != 1 not implemented
      • List slice-store with non-iterable on RHS is not implemented
      • List store with step != 1 not implemented
    • str
      • UnicodeDecodeError not raised when expected
      • Start/end indices such as str.endswith(s, start) not implemented
      • Attributes/subscr not implemented
      • str(…) with keywords not implemented
      • str.ljust() and str.rjust() not implemented
      • None as first argument for rsplit such as str.rsplit(None, n) not implemented
      • Instance of a subclass of str cannot be compared for equality with an instance of a str
      • Subscript with step != 1 is not yet implemented
    • tuple
      • Tuple load with step != 1 not implemented
  • Modules
    • array
      • Looking for integer not implemented
      • Array deletion not implemented
      • Subscript with step != 1 is not yet implemented
    • deque
      • Deque not implemented
    • json
      • JSON module does not throw exception when object is not serialisable
    • struct
      • Struct pack with too few args, not checked by uPy
      • Struct pack with too many args, not checked by uPy
    • sys
      • Overriding sys.stdin, sys.stdout and sys.stderr not possible
• MicroPython license information