🔧 Board Overview

This custom dev board is built around the ATtiny1624 microcontroller. It includes onboard power regulation and is UPDI-programmable via an Arduino Nano or similar.

⚙️ Key Specs

✅ Microcontroller: ATtiny1624

• Architecture: AVR (tinyAVR 1-series)

• Flash: 16 KB

• SRAM: 2 KB

• EEPROM: 256 Bytes

• I/O Pins: 18 GPIOs

• Interfaces: UPDI, SPI, I²C, USART

• Clock: Up to 20 MHz internal oscillator

• Operating Voltage: 1.8V – 5.5V (board regulated to 5V)

🔌 Power Supply

• Input Voltage (VIN): 4V to 15V via terminal block labeled VIN 4–15V 

• Regulator IC: 

  • Buck-boost converter

  • Regulates input to stable 5V

• Protection Diode:  for reverse polarity protection

🔄 Programming Interface: UPDI

• Pin PA0 on ATtiny1624 serves as the UPDI programming pin.

🛠️ Programming with Arduino Nano (as UPDI programmer)

You can use an Arduino Nano to program the ATtiny1624 via UPDI using the following method:

✅ Required:

• Arduino Nano

• PyUPDI script or megaTinyCore in Arduino IDE

🔌 Wiring

💻 Programming Steps

1. Install megaTinyCore in Arduino IDE.

2. Select:

   • Board: ATtiny1624/1626/1627

   • Programmer: jtag2updi (megaTinyCore)

3. Burn bootloader (to set fuses).

4. Upload sketches via UPDI.

🔌 I/O Headers

There are two 8-pin headers:

• U7 (bottom side): PA4–PA7, PB2–PB3, and power pins (5V, GND)

• U8 (top side): PA0–PA3, PB0–PB1, PA0 doubles as UPDI