Difference between revisions of "QT Py (RP2040 based)"

Revision as of 13:38, 11 July 2022

RP2040 QT Py

Two manufacturers
- Adafruit QT Py RP2040 Product page
- Seeed XIAO RP2040 Product page
USB Type C connector
RP2040 32-bit Cortex M0+ dual-core
Runs at ~125 MHz
264 KB RAM
SPI FLASH chip for storing files and CircuitPython/MicroPython code storage
- 8 MB - Adafruit
- 2 MB - Seeedstudio
No EEPROM
Can be used with C/C++ (Arduino), MicroPython, or CircuitPython
Built-in RGB NeoPixel LED
13 GPIO pins (11 breakout pads and two QT pads):
- Four 12 bit ADCs (one more than Pico)
- I2C port
  - 2 I2C: 1 on QT pins, one on the (Adafruit) breakout pads - Adafruit
  - 1 I2C on XAIO
- SPI and UART peripherals, in standard QT Py locations,
- PWM outputs on every IO pin - for servos, LEDs, etc
- There are 6 GPIO in consecutive order for PIO compatibility
3.3V logic and power 600 mA
Both Reset button and Bootloader select buttons for quick restarts (no unplugging-replugging to relaunch code)

Pins (RP2040)

Pins are mapped differently in MicroPython between Seeeduino XIA and Adafruit QT Py
The Python board module virtualizes the difference

Adafruit RP2040

Adafruit QT Py RP2040 Product page

3V

Regulated output from the onboard regulator. You can draw 500mA

5V

5v out from the USB port.
Voltage input
- Requires external diode
  - Schottky, signal, power
  - Between external power source and this pin
  - Cannot power the USB port by supplying 5V to this pin
    - There is a protection diode that prevents the 5V from reaching the USB connector.
    - This is to protect host computer USB ports, etc.

A0 / D0 - Digital/analog GPIO pin 0

Digital I/O 0
GPIO29 in MicroPython
Analog In 0
True analog output with 10 bit precision
Does not have PWM
Capacitive touch input.

A1 / D1 - Digital/analog GPIO pin 1

Digital I/O 1
GPIO28 in MicroPython
Analog In 1
Capacitive touch input
AREF pin.

A2 / D2 - Digital/analog GPIO pin 2

Digital I/O 2
GPIO27 in MicroPython
Analog In 2
PWM
Capacitive touch input.

A3 / D3 - Digital/analog GPIO pin 3

Digital I/O 3
GPIO26 in MicroPython
Analog In 3
PWM output
Capacitive touch input.

SDA / D4

Digital I/O 4
I2C SDA pin
PWM output
GPIO24 in MicroPython
No analog on this pin
No pull up on this pin
When using with I2C requires an external 2.2K-10K pullup to 3.3V.

SCL / D5

Digital I/O 5
I2C SCL
GPIO25 in MicroPython
No analog on this pin
No pull up on this pin
When using with I2C requires an external 2.2K-10K pullup to 3.3V.

TX / A6 / D6

Digital I/O 6
Transmit (output) for Serial1
GPIO20 in MicroPython
Analog 6
PWM output
Capacitive touch input

RX / A7 / D7

Digital I/O 7
Receive (input) for Serial1
GPIO5 in MicroPython
Analog 7
PWM output
Capacitive touch input

SCK / A8 / D8

Digital I/O 8
SPI SCK pin
GPIO6 in MicroPython
Analog 8
PWM output

MISO / A9 / D9

Digital I/O 8
SPI MISO pin
GPIO4 in MicroPython
Analog 8
PWM output

MOSI / A10 / D10

Digital I/O 10
SPI MOSI pin
GPIO3 in MicroPython
Analog 10
PWM output

NeoPixel

NEOPIXEL LED Features
- Individually addressable and programmable RGB LEDs
- Operating voltage: 3.3V to 5V
- Power consumption: 60mA per LED at full brightness
- Communication: PWM through data pin
- Driver IC: WS2812
Data = Pin 11
Power = Pin 12 - set low for low power usage
By default pin 12 is set high by Arduino/CircuitPython
NeoPixel Code example

import board
import neopixel

pixels = neopixel.NeoPixel(board.NEOPIXEL, 1)
# fill((rVal, gVal, bVal))
# rVal, gVal, bVal = red/green/blue values (0-255)
pixels.fill((255, 0, 0))  # Note double parens

Seeeduino RP2040

There are 14 GPIO PINs on XIAO RP2040, on which there are 11 digital pins, 4 analog pins, 11 PWM Pins,1 I2C interface, 1 UART interface, 1 SPI interface, 1 SWD Bonding pad interface.

3V

Regulated output from the onboard regulator. You can draw 500mA

5V

5v out from the USB port.
Voltage input
- Requires external diode
  - Schottky, signal, power
  - Between external power source and this pin
  - Cannot power the USB port by supplying 5V to this pin
    - There is a protection diode that prevents the 5V from reaching the USB connector.
    - This is to protect host computer USB ports, etc.

A0 / D0 / P26 - Digital/analog GPIO pin 0

board.D0
board.A0
P26 in Arduino/MicroPython
True analog output with 10 bit precision
PWM output

A1 / D1 / P27 - Digital/analog GPIO pin 1

board.D1
board.A1
P27 in Arduino/MicroPython
PWM output

A2 / D2 / P28 - Digital/analog GPIO pin 2

board.D2
board.A2
P28 in Arduino/MicroPython
PWM output

A3 / D3 / P29 - Digital/analog GPIO pin 3

board.D3
board.A3
P29 in Arduino/MicroPython
PWM output

SDA / D4 / P6

board.D4
board.SDA
P6 in Arduino/MicroPython
I2C SDA pin
PWM output
No pull up on this pin
When using with I2C requires an external 2.2K-10K pullup to 3.3V.

SCL / D5 / P7

board.D5
board.SCL
P7 in Arduino/MicroPython
I2C SCL
No pull up on this pin
When using with I2C requires an external 2.2K-10K pullup to 3.3V
PWM output

TX / D6 / P0

board.D6
board.TX
Transmit (output) for Serial1
P0 in Arduino/MicroPython
PWM output

RX / D7 / P1

board.D7
board.RX
Receive (input) for Serial1
P1 in Arduino/MicroPython
PWM output

SCK / D8

board.D8
board.SCK
SPI SCK pin
P2 in Arduino/MicroPython
PWM output

MISO / D9 / P4

board.D8
board.MISO
SPI MISO pin
P4 in Arduino/MicroPython
PWM output

MOSI / D10 / P3

board.D10
board.MOSI
SPI MOSI pin
P3 in Arduino/MicroPython
PWM output

On-board LEDs

Red Power LED
USER LED (RGB)
- RED - P17
  - board.LED_RED
- GRN - P16
  - board.LED_GREEN
  - LED_BUILTIN in Arduino
- BLU - P25
  - board.LED_BLUE
- Code to Blink 3 LEDs
NEOPIXEL LED Features
- Individually addressable and programmable RGB LEDs
- Operating voltage: 3.3V to 5V
- Power consumption: 60mA per LED at full brightness
- Communication: PWM through data pin
- Driver IC: WS2812
- NEOPIXEL Power - P11 - set low for low power usage
  - board.NEOPIXEL_POWER
- NEOPIXEL Data - P12
  - board.NEOPIXEL
- NEOPIXEL Demo

Programming

The RP2040 can be programmed in several languages/environments
- C/C++
- CircuitPython - best choice in most cases
- MicroPython

C/C++

Can program in C/C++ using
- Arduino IDE
- Pico C++ SDK

C/C++ Adafruit RP2040 - Arduino

Arduino IDE Setup
Add the URL to the the Additional Boards Manager URLs

https://github.com/earlephilhower/arduino-pico/releases/download/global/package_rp2040_index.json

Tools > Board > Boards Manager
Search for RP2040
Scroll down to the Raspberry Pi Pico/RP2040 by Earle F Philhower, III entry
Click Install to install it
Tools > Boards menu
Navigate to the Raspberry Pi RP2040 Boards menu and choose Adafruit QT Py RP2040

C/C++ Seeeduino RP2040 - Arduino

Arduino IDE Setup for Seeeduino RP2040 version
- Requires Arduino IDE version 1.8 or higher
- Add the URL to the the Additional Boards Manager URLs

https://files.seeedstudio.com/arduino/package_seeeduino_boards_index.json

Arduino Repository

C/C++ RP2040

Raspberry Pi Pico C/C++ SDK

CircuitPython

CircuitPython is a derivative of MicroPython
CircuitPython is the best choice in most use-cases
- Board specific support for both Seeed XAIO and Adafruit QT Py cards
Welcome To CircuitPython - Adafruit tutorial
Autorun code - CircuitPython looks for a code file on the board to run
- There are four options: code.txt, code.py, main.txt and main.py
- CircuitPython looks for those files, in that order, and then runs the first one it finds
Mu code editor
- Mu editor download

CircuitPython for Adafruit QT Py RP2040

Install CircuitPython on Adafruit QT Py RP2040

Adafruit CircuitPython Download page
- Running v7.3.0
Hold down the BOOT (right) button while plugging it into USB
Download UF2 from Adafruit QT Py CircuitPython RP2040
Drive will open
Drop UF2 onto drive
Blink program
- QT_Py_blink.py

Updating CircuitPython on Adafruit QT Py RP2040

Save the contents of CIRCUITPY, just in case
Double-click the reset button to show the BOOT drive
Drag the update-bootloader .uf2 file to the BOOT drive
Wait a few tens of seconds for the bootloader to update; the BOOT drive will reappear
Check INFO_UF2.TXT to verify that the bootloader version has been updated. Then you will need to reload CircuitPython.
Update mpy files

CircuitPython for Seeed XIAO RP2040

XIAO RP2040 with CircuitPython
Our GitHub repo
Use Thonny IDE
- Left click bottom right corner
- Select CircuitPython (generic)
- Left click bottom right corner
- Select Configure Interpreter
- Select USB Serial Device (COM<x)
Pins list

import board
dir(board)
['__class__', '__name__', 'A0', 'A1', 'A2', 'A3', 'D0', 'D1', 'D10', 'D2', 'D3', 'D4', 'D5', 'D6', 'D7', 'D8', 'D9', 'I2C', 'LED', 'LED_BLUE', 'LED_GREEN', 'LED_RED', 'MISO', 'MOSI', 'NEOPIXEL', 'NEOPIXEL_POWER', 'RX', 'SCK', 'SCL', 'SDA', 'SPI', 'TX', 'UART', 'board_id']

>>> print(board.board_id)
seeeduino_xiao_rp2040

Install CircuitPython on Seeed XIAO RP2040

Hold down the "BOOT" button. (The "B" is written on the board shown to the right)
Connect the XIAO RP2040 to your computer while you still pressing the button.
The computer then will appear a disk driver(RP1-RP2)
Download the XIAO-RP2040-CircuitPython.uf2 file for XIAO RP2040
Drag the .uf2 file to the disk driver("RP1-RP2")
Check the disk drive if the name has changed to "CIRCUITPY" (takes a few seconds)
Free memory

>>> import gc
>>> gc.mem_free()
208128
>>> import time
>>> gc.mem_free()
207952

CircuitPython Example Code

i2cscan.py - Print list of I2C devices found

SSD1306 Display Examples

ssd1306_TextFB.py - Displays 21 columns and 8 rows of text
ssd1306_bouncing_ball.py - Bounce a ball
ssd1306_framebuftest.py - Frame buffer demo
ssd1306_simpletest_FB.py - Draws 3 pixels

Digital I/O Examples

Land Boards I2CIO-8 (MCP23008) Examples

GitHub Repo
- I2CIO8.py Demo code - Bounce an LED across MCP23008 card output pins
- I2CIO8_RW.py - Read jumpers, write back LEDs

>>> dir(i2c)
['__class__', '__enter__', '__exit__', 'deinit', 'readfrom_into', 'scan', 'try_lock', 'unlock', 'writeto', 'writeto_then_readfrom']

Land Boards SWLEDX8-I2C (MCP23017) Examples

SWLEDX8.py = Control the SWLEDX8-I2C card

Land Boards PROTO16-I2C (MCP23017) Examples

PROTO16_Blink.py - Control the PROTO16-I2C card

MicroPython

MicroPython on XIAO RP2040

XIAO RP2040 with MicroPython
Software Setup

Download and Install the latest version of Thonny editor according to your operating system
Launch the Thonny IDE
Click "Tools→Options" to open the settings.
Step 4. Chose the "Interpreter" interface and select the device as "MicroPython(Raspberry Pi Pico)" and the port as "Try to detect prot automatically"
Press and hold the "BOOT" button and then connect the XIAO RP2040 to the PC through the Type-C cable. If it works well, there is an "RPI-RP2" desk shown on the PC.
Press the "Stop/Restart Backend" button and there will be a pop-up window that helps you install the MicroPython firmware on the board. The XIAO RP2040 uses the same chip as the Raspberry Pi Pico, thereby the XIAO RP2040 is compatible with Pico's MicroPython files.
Write code (Neopixel example)
Upload the codes by clicking the "Run current script" button. For the first time, Thonny will ask where you want to save your codes file. Both This Computer and Raspberry Pi Pico are fine.

MMBASIC on XIAO RP2040

Hardware
- QTPy49 card with Seeed Studio XIAO RP2040
- SD CARD X49
BASIC Interpreter for the Raspberry Pi Pico running on XIAO RP2040
- MMBasic is a Microsoft BASIC compatible implementation of the BASIC language with floating point, integer and string variables, arrays, long variable names, a built in program editor and many other features
- 8 Flash locations for storage
- Support for SD Card

MMBASIC Credits

Peter Mather led the project, ported the MMBasic interpreter to the Raspberry Pi Pico and wrote the hardware device drivers. Geoff Graham wrote the MMBasic interpreter and the manual. Mick Ames wrote the PIO compiler and its corresponding documentation.

Install MMBASIC on Seeed XIAO RP2040

Hold down the "BOOT" button
- The "B" is written on the board shown to the right
Connect the XIAO RP2040 via USB C cable to your computer while still pressing the button
The computer then will appear a disk driver(RP1-RP2)
Download the PicoMite_Firmware.zip
Drag the .uf2 file to the disk drive ("RP1-RP2")
Card will re-boot
Connect in TeraTerm over serial
Free memory

> print mm.ver
 5.070501

> memory

Program:
   0K ( 0%) Program (0 lines)
 124K (100%) Free

RAM:
   1K ( 1%) 3 Variables
   0K ( 0%) General
 155K (99%) Free

SD Card Wiring

SD_CARD_X49 card
- NO5V jumper installed

Signal	SD_CARD_X49	QTPy49 conn	QTPy GP	PiPico Pin
SPI_SCLK	J1-3	J3-6	GP2	GPIO2
SPI_MOSI	J1-4	J3-4	GP3	GPIO3
SPI_MISO	J1-2	J3-5	GP4	GPIO4
SPI_SS	J1-5	J9-3	GP26	GPIO26
GND	J1-1	J9-1
VCC (3.3V)	J1-7	J9-2

On-Board LED

No Built-in support in MMBASIC for the on-board NEOPIXEL
Red, Green, Blue LED
Pull Low to turn on RGB LED bits
At-boot - RGB LED blinks Cyan/Green by MMBASIC
Red LED = GP17
Green LED = GP16
Blue LED = GP25 (Used by MMBASIC)

SETPIN GP17, DOUT:' Red LED
SETPIN GP16, DOUT:' Green LED
SETPIN GP25, DOUT:' Blue LED
PIN(GP17)=1:' Turn off Red LED
PIN(GP25)=1:' Turn off Blue LED
PIN(GP16)=1:' Turn off Green LED
PIN(GP17)=0:' Turn on Red LED
PIN(GP25)=0:' Turn on Blue LED
PIN(GP16)=0:' Turn on Green LED

GPIO from MMBASIC

QTPy49 Marking	GPIO
A0	GP26 (SD_SS)
A1	GP27
A2	GP28
A3	GP29
I2C_SDA	GP6
I2C_SCL	GP7
RX	GP1
TX	GP0

MMBASIC - Using Pins

Digital I/O

SETPIN GP27, DIN:' Digital Input
SETPIN GP28, DOUT:' Digital Output
PIN(GP28) = 1:'Digital output

Analog Input

SETPIN GP29, AIN:' Analog Input

SETPIN(s) for Serial and I2C

SETPIN GP1, GP0, COM1
SETPIN GP6, GP7 I2C2

SD Configuration

OPTION SYSTEM SPI GP2, GP3, GP4
OPTION SDCARD GP26

Verify it is working

> FILES
A:/
   <DIR>  basic
   <DIR>  bmps
   <DIR>  demos
   <DIR>  games
   <DIR>  jpegs
   <DIR>  lbcards
   <DIR>  performance
   <DIR>  wave
8 directories, 0 files

RS-232 (option)

DCE or DTE card
Command to use serial

OPTION SERIAL CONSOLE GP0, GP1

QT Py Breakout Board

Built onto GRID49 card
Socket for QT Py
QT Py pins brought to header strips
3.3V power distribution on 2x8 header

Pins (CCW direction)

S12 = A0
R12 = A1
Q12 = A2
P12 = A3
N12 = SDA
M12 = SCL
L12 = TX
L1 = RX
M1 = SCK
N1 = MI
P1 = MO
Q1 = 3.3V
R1 = GND
S1 = 5V
A6=B6=C6=D6=E6=F6=G6=H6 = GND
A7=B7=C7=D7=E7=F7=G7=H7 = 3.3V

QTPy49 Board

QTPy49