It is not only calculator, it is complete standalone python computer with python firmware and multiple selectable apps on startup.
- write and execute scripts on device
- Optimized for circuitpython
- some hardware GPIO Uart RX/TX or I2C SDA/SCL
- SD card storage
- interactive REPL
- IPS 2.8" COLOR LCD
- 49+1 tactile soft press keyboard in matrix 7x7
- no 3D prints = durable PCB enclosure
Working software features:
- Boot menu
- Text Editor
- Turtle graphics programming
- Plot graph
- play mp3
- Retro computer emulation on separated firmwares
already working emulation ZX128, ZX48, ZX81, C64, Atari800
TODO software features:
- text/ebook viewer
- longer text editor
What you can learn on this board?
- assembly and soldering skills, you need just solder one Raspberry pi PICO module and 50 switches, display soldering need some skills but I selected one with low count wires
- circuitpython or micropython
- Arduino programming
- C programming
- QWERTY keyboard matrix reading
- complex input/output HID processing read keyboard data,
- create and display graphics
- save and processing files
- work with I2C sensors or process GPS data
- RTC clock and alarms
- With Raspberry Pi PICO W play with WiFi and bluetooth
- Testing if is possible to use ESP32s3 on pico pinout compatible module
- power management, sleep, wake by alarm, wake on receive
Production and marketing plans:
Hardware is very simple and easy to solder by hand, low active component count make it very attractive as learn to solder kit.
Plan is produce partially assembled kits with already soldered display, and DIY soldering switches.
Why TH tactile switches? because is very important to precise align with front cover plate and this can be little hard with hand.
Raspberry Pi PICO Advantages:
- Unbrickable ROM bootloader
- Drang&drop initial setup
- Easy soldering
- integrated power supply
- onboard USB connector
- testpoints for connect USB-A for as USB host
- effective buck/boost powering
- use Pico W with wireless without changes
- Waveshare alternative Rp2040plus have lion charging + USB-C and double flash memory
- Circuitpython with libraries for almost everything with tutorials and examples
- no competition with working pocket computer
- compact encapsulated design
- QWERTY keyboard, much user friendly than ABCD
- officially supported Raspberry Pi PICO standard unmodified circuitpython
- extremely simple just one easy solder module and buttons, cheap and low component count
- low power consumption
- native circuitpython apps, no monster OS behind
- multiple apps on device and boot menu
- GPIO for external sensors readings etc in school lab.
- large 2.8"" all angles views IPS color graphics display 320x240
- no community, no users
- my programming knowledge is limited (I quickly learning)
- display soldering need little more skills (semi-assembled kit may can help)
- with good manufacturing plan it ca be very good education toy
- I haven't caught competition in this segment, but if it appears with good marketing and a production plan may kill this simple idea
- as everywhere, the main competition are touch screens and mobile phones
PYPRCA vs Numworsk
You say that "the main competition are touch screens and mobile phones"
The shop you bought you display at has a variant of the display with the touchscreen option TFT HC28010-DCT it is a little more expensive but not too much. Didn't you consider using this one?
I think there is a mistake in the BOM DTS-64K seems to not exist.
There are DTS-644 or DTS-648 but these one have a square button not a round one.
7mm ones with a round button are DTS-63K