Raspberry Pi Pico

Raspberry Pi Pico Features

Raspberry Pi Pico is a low-cost, high-performance microcontroller board with flexible digital interfaces. Key features include:

• RP2040 microcontroller chip designed by Raspberry Pi in the United Kingdom
  • Dual-core Arm Cortex M0+ processor, flexible clock running up to 133 MHz
  • 264KB of SRAM
  • 2MB of on-board Flash memory
• Castellated module allows soldering direct to carrier boards
• USB 1.1 with device and host support
• Low-power sleep and dormant modes
• Drag-and-drop programming using mass storage over USB
• 26 × multi-function GPIO pins
• 2 × SPI, 2 × I2C, 2 × UART, 3 × 12-bit ADC, 16 × controllable PWM channels
• Accurate clock and timer on-chip
• Temperature sensor
• Accelerated floating-point libraries on-chip
• 8 × Programmable I/O (PIO) state machines for custom peripheral support

Repositories

• My Raspberry Pi Pico GitHub repository - Home
  • My MicroPython GitHub repository
  • My CircuitPython GitHub repository

Pinout

Reference Documents

• Raspberry Pi Pico data sheet
• RP2040 Datasheet
• Hardware Design Guide
• Getting started with Raspberry Pi Pico - C/C++ development with Raspberry Pi Pico and other RP2040-based microcontroller boards
• Raspberry Pi Pico C/C++ SDK
• Raspberry Pi Pico Python SDK

Adapter Cards

• There are three versions of this card
  • PiPicoMite01 (this version)
    • Has 16-bit port I/O expander
    • 120x70mm with (4) 6-32 mounting holes
  • PiPicoMite02
    • Has 32-bit port I/O expander(s)
    • 95x95mm with (4) 6-32 mounting holes
  • PiPicoMite03
    • 99.5x69.5mm - Fits into extruded Aluminum Enclosure
    • Fully functional, reduced cost

PiPicoMite01

• PiPicoMite01

PiPicoMite02

PiPicoMite02

PiPicoMite03

PiPicoMite03

PicoVGA01

PicoVGA01

In Small Plastic Project Box

• CircuitSetup Breadboard

• Fits in 100x60x25mm Project Box
• Socketed Raspberry Pi Pico
• All Pico pins brought to Male Header pins
• Power/Ground distribution
• 5V jack
  • VSYS connection with Schottky diode
• Can by Mounted on ODAS Adapter card

Cut Etch / Add wires

• Cut etch from + near jack to board side + connections
• Verify cut with jumper (center pin power jack to + on both sides)

• Add TIE - jumper to ties grounds on both sides together

• Add Power jumper between the two sides

• Add Ground connection Pico pin 38 to - hole near strip
• Add 3.3V Power connection Pico pin 36 to + hole near strip on other side

Schematic Symbol

Pin Table

Pico Pin	BB Pin	Signal		Pico Pin	BB Pin	Signal
1	30	GP0		40	30	VUSB
2	29	GP1		39	29	VSYS
3	28	GND		38	28	GND
4	27	GP2		37	27	3V3EN
5	26	GP3		36	26	3V3OUT
6	25	GP4		35	25	ADCVREF
7	24	GP5		34	24	GP28
8	23	GND		33	23	GND
9	22	GP6		32	22	GP27
10	21	GP7		31	21	GP26
11	20	GP8		30	20	RUN
12	19	GP9		29	19	GP22
13	18	GND		28	18	GND
14	17	GP10		27	17	GP21
15	16	GP11		26	16	GP20
16	15	GP12		25	15	GP19
17	14	GP13		24	14	GP18
18	13	GND		23	13	GND
19	12	GP14		22	12	GP17
20	11	GP15		21	11	GP16

Software Development

• C/C++
• Forth
• MicroPython
• CircuitPython

C/C++

C/C++ SDK

• SDK Easier Install - working following instructions and comments after...

Mbed library with Arduino IDE

• Program RPi Pico using Mbed library with Arduino IDE
• Arduino Core mbed 2.0 supports Raspberry Pi Pico

Forth

• zeptoforth
  • zeptoforth is a Cortex-M Forth, targeted at the Raspberry Pi Pico
  • zeptoforth Wiki page
• zeptoforth includes the following features:
  • A priority-scheduled preemptive multitasker
  • Semaphores
  • Locks, with priority inversion handling
  • Message-oriented queue channels
  • Message-oriented rendezvous channels, aka "fchannels"
  • Message-oriented bidirectional synchronous reply channels, aka "rchannels"
  • Byte-oriented streams
  • Interrupt service handler-safe channels, aka "schannels"
  • Task notifications
  • Action scheduler support
  • Multicore support (on the Raspberry Pi Pico)
  • Double cell and fixed point numeric support
  • Lambda/quotation expressions
  • A disassembler
  • SysTick support
  • User-reconfigurable processor exception vector support
  • Interrupt-driven serial IO
  • GPIO support (including EXTI support on STM32 microcontrollers)
  • Maps, including counted string and integer-keyed maps
  • Heap allocators
  • Memory pool allocators
  • Task pool allocators
  • Action pool allocators
  • Temporary storage allocators (used to provide immediate string constants)
  • A line editor
  • LED drivers
  • Quad SPI flash storage support (on the STM32F746 DISCOVERY board and the Raspberry Pi Pico)
  • A block editor (on the STM32F746 DISCOVERY board and the Raspberry Pi Pico)
  • Random number generator support
  • Pseudorandom number generator support (using the TinyMT32 PRNG)
  • Programmable input/output support (on the Raspberry Pi Pico)
  • Optional swdcom support

Running MicroPython

• MicroPython page
• Raspberry Pi Pico with MicroPython
• Python SDK
• Quick MicroPython reference for the RP2
• RP2 Python Library Modules
• Card has 264KB of SRAM
• Free memory under MicroPython plus various module sizes

>>> import gc
>>> gc.mem_free()
182624
>>> import time
>>> gc.mem_free()
178544
>>> import machine
>>> gc.mem_free()
174304
>>> 

• To compare QT Py on the SAMD21 has 19KB free
• QT Py on XAIO RP2040 has 208,128 free

Python File System

• Internal Flash File System
  • Little FS
  • 1.44MB space
  • Blocks are 4KB
  • 352 Blocks on Internal File System
• os functions

import os
os.[TAB]
os.dir()
os.mkdir("newdir")
os.getcwd()
os.mkdir("newdir")
os.chdir('..')
os.listdir()
os.statvfs('/')
os.uname()
os.remove('file2remove')
os.rename('old','new')

• Using files

f = open('filename','w')
f.write('data to add')
f.read()
f.close()

I2C Scanner

import machine

# Create I2C object
i2c = machine.I2C(0, scl=machine.Pin(17), sda=machine.Pin(16))

# Print out any addresses found
devices = i2c.scan()

if devices:
    for d in devices:
        print(hex(d))

Running PicoMite (MaxiMite) BASIC

• Two versions
  • PicoMiteVGA, PS/2 version
  • PicoMite USB-Serial with SD Card

Running PicoMite (MaxiMite) BASIC (VGA, PS/2)

The PicoMiteVGA boots straight into the MMBasic prompt. At which point you can enter, edit and save the program, test BASIC commands and run the program. MMBasic is a Microsoft BASIC compatible implementation of the BASIC language. It is full featured with floating point, 64-bit integers and string variables, long variable names, arrays of floats, integers or strings with multiple dimensions, extensive string handling and user defined subroutines and functions. Typically it will execute a program up to 100,000 lines per second. Embedded compiled C programs can be used for even higher performance.

The PicoMiteVGA is a Raspberry Pi Pico with VGA output, PS2 keyboard input, SD card storage and running the free MMBasic interpreter.

The PicoMiteVGA firmware reserves eight program storage "slots" in the Raspberry Pi Pico flash memory. Programs can be saved and retreived from these without the need for any additional storage.

You can draw grapics in 16 different colours, show text in multiple fonts and save your programs to an SD card. For more storage SD cards can be connected with full support for these built into MMBasic including the ability to open files for reading, writing or random access and loading and saving programs. SD cards connect directly to the Raspberry Pi Pico and the firmware will work with cards up to 32GB formatted in FAT16 or FAT32. The files created can be read and written on personal computers running Windows, Linux or the Mac operating system.

The PicoMiteVGA boots straight into the MMBasic prompt. At which point you can enter, edit and save the program, test BASIC commands and run the program.

The User Manual is a comprehensive description of the PicoMiteVGA including circuits for interfacing the VGA monitor, keyboard and SD card.

> memory
Program:
  13K (10%) Program (485 lines)
  95K (90%) Free

RAM:
   0K ( 0%) 0 Variables
   0K ( 0%) General
 140K (100%) Free

PiPicoMite01 Card

• PiPicoMite01

Configuration

OPTION KEYBOARD US
OPTION SDCARD GP13, GP10, GP11, GP12
OPTION AUDIO GP6, GP7
OPTION COLOURCODE ON

PiPicoMite02 Card

• PiPicoMite02

Configuration

> OPTION LIST
OPTION COLOURCODE ON
OPTION KEYBOARD US
OPTION SDCARD GP13, GP10, GP11, GP12
OPTION AUDIO GP6, GP7
option system i2c gp0, gp1

PiPicoMite03 Card

• PiPicoMite03

Configuration

> OPTION LIST
OPTION COLOURCODE ON
OPTION KEYBOARD US
OPTION SDCARD GP13, GP10, GP11, GP12
OPTION AUDIO GP6, GP7
OPTION SYSTEM I2C2 GP14, GP15

Running PicoMite (MaxiMite) BASIC (USB-Serial)

• Incompatible connections to SD Card from VGA version
  • VGA version does everything this version does since it can be run via the USB console
• "Boot to MM BASIC" on the Raspberry Pi Pico with VGA
• BASIC Interpreter for the Raspberry Pi Pico - USB
• SD Card Connections

PicoMite SD Card Wiring

• Install NO5V jumper

SD_Socket	PIN	SD-J1	Pi-Pico	Pico-Pin	Colour
3	GND	1	GND	GND	BLK
7	MISO	2	GPIO16	21	BRN
5	SCLK	3	GPIO18	24	ORA
2	MOSI	4	GPIO19	25	YEL
1	SLV SEL	5	GPIO22	29	WHT
4	VCC	7	3.3V	N/C
6	GND	N/C	GND

PicoVGA

• PicoVGA01

Running RP2040 Doom

• RP2040 Doom

Running VGA

Hardware Design Guide Section 3.2

Raspberry Pi Pico Software Repositories

• Raspberry Pi Pico Foundation Files
• Arduino Pico
  • Arduino Pico Docs