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

PiPicoMite03

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

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))

Interesting Applications

Running PicoMite (MaxiMite) BASIC

Two versions
- VGA, PS/2 version
- 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

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

Raspberry Pi Pico

Contents