Picomputer - Universal Pocket Computer

I am always dreaming about pocket computers, now thanks to Raspberry PICO I can create a very universal
low-power device that you can have all under your control.

It is a universal computer specially designed for Raspberry Pi PICO, exists in more variations but the main feature is a QWERTY keyboard.

I am take care to minimize external components, use maximum features integrated on PICO board: Power switch use enable input on PICO, ON-BOARD LED is visible thanks to missing solder mask, PICO boot button hole. Overall dimensions are smallest as possible.

The project is divided into three main "groups" or maybe is a fusion of three different purposes.

•  RETROCOMPUTER Retro computer emulation
  - ZX spectrum 48k/128k
  - C64
  - Atari 800
• COMMUNICATOR
  - Sending/receiving messages over LoRa radio module
• POCKET COMPUTER
  - Universal programming learning toy

Tested in circuitpython

• detect power supply voltage and USB connection
• MP3 Playback
• Display backlight brightness
• send message to another device via LoRa Radio
• QWERTY keyboard
• multi lines text editor
• read / store files to internal system
• safe boot
• GPS parse
• I2C sensors
• display BMP images
• run different application after boot ti make more universal and versatile ... you can have APPS!!!

Retro computer machine emulators 

• https://github.com/Jean-MarcHarvengt/MCUME/tree/master/MCUME_pico
• https://github.com/fruit-bat/pico-zxspectrum

FEATURES:

• Smallest as possibly 100x69x8mm
• Absolute minimum components.
• Auxiliary USB-C for power only.
• Access to boot button
• flashing logo with internal led.
• IPS 240x240 display / 320x240. 3 types or more
• Piezo Speaker
• free on GPIO header
• Reset button
• power switch controlling internal buck-boost
• micro SD card
• optional RFM95 LoRa radio
  **you can use RFM95 or micro SD not both !!!! they sharing same GPIO**

PICOmputer exist in more enclosue variations, this is latest with full PCB box

SWOT analysis

Strengths:

• no competition
• simple as possible
• cheap
• beautiful design (I'm shameless)
• qwerty keyboard
• HD IPS display - onboard
  any display, iPS, TFT, OLED, eInk by wires, need just redesign front panel
• circuitpython
• micropython
• arduino core

Weaknesses:

• my programing knowledge is basic

Opportunities:

• GUI learning tool
• native USB
• ETHENRNET possibility, there is big opportunity in application where is needed something like networking plug and play ... quick connect to LAN with DHCP configuration, etc. simple terminal
• standalone computer programmable in basic or micropyton

Threats:

-please write in comments, I am blinded by my enthusiasm

Supported displays:

• 12pin st7789 IPS 240x240 via flex cable 1.3" inch
• 12pin st7789 IPS 240x240 via flex cable 1.54" inch
• 12pin st7789 IPS 280x240 via flex cable 1.69" inch round corner
• 12pin st7789 IPS 320x240 via flex cable 2" inch
• 8pin st7789 IPS 240x240 via header
• any display with popular china module pinout GND,VCC,SCK,DAT,RES,DC,CS,BACKLIT

Required components

| Component | pcs | description | note |

| -------- | --------:|:--------:| ---------------- |

| Raspberry PICO| 1 | main green board | - |

| DTS63K| 37 | tactile switch 7mm height, 1N| Or another 1N force is very comfortable to press |

| RFM95W| 1 | radio module with frequency for your country | If you build Armachat |

| SD card reader| 1 | generic aliexpres part | If you build Retro computer emulator |

| 2.0" IPS screen| 1 | 12PIN 320x240 ST7789V| - |

| BSS123| 1 | Transistor | display backlight |

| 10R 0603| 1 | Resistor | display backlight |

| 4k7| 1 | Resistor | display backlight |

| LPT1109DS| 1 | PIEZO | PIEZO sound beeper |

| JS202011CQN C&K or MSS-2235 NINIGI| 1 | Side Switch| For power off (PICOmputer work without) |

Almost all components and alternatives except bag of switches

Latest version use bright IPS display with rounded corners, with alternative PICO board form waveshare you can get USB-C, double flash memory and battery charging without any software/hardware modifications