TENTAKU is a calculator with a numpad layout that uses mechanical keyswitches.
- ATMEGA328P used as main controller
- TM1638 used to control LEDs and 7-segment displays
Please flash at your own risk. I'm working on this as a side project and I can't guarantee that this won't mess up your board. I'm not responsible for anything (good or bad) that happens as a result of this code. If you don't feel 100% comfortable, DO NOT FLASH THIS FIRMWARE.
Make sure you make a backup first by writing out the flash memory to a file format of your choose with a command like:
avrdude -p m328p -P usb -c usbtiny -U flash:r:flash.hex:i (for Intel HEX)
avrdude -p m328p -P usb -c usbtiny -U flash:r:flash.bin:r (for raw binary)
To build your own file, just run make in the project root. The output is in ./build/main.hex.
You should know how to flash your file if you've perfomed a backup, so I'm leaving this as an exercise for the reader.
Please feel free to open an issue if you have problems.
- Three registers: DDRD, PORTD, PIND, X is bit
- DDRDX controls data direction (sets input or output)
- PORTDX is written to when data needs to be sent
- PINDX is read from when data is received
- 5 (PORTD5) - DIO (data input/out)
- 6 (PORTD6) - CLK (clock)
- 7 (PORTD7) - STB (strobe/chip select)
Listed from left to right with the board upright:
- ~CS (PORTB2)
- SCK (PORTB5)
- MISO (PORTB4)
- MOSI (PORTB3)
- GND
- VCC