Single-chip microcomputer chip: ATmega128A;Filter inductors and capacitors have been added to the AD conversion reference voltage;Different frequencies of external crystal oscillators can be through ; All IO ports are led out and marked;Both the ISP and JTAG interfaces are led out and marked;Reliable reset circuit;Two leds are LED out from PA1 and PA0 for simple testing;The DC socket or pin is powered by 5V;PCB board size: 52.3mmx80mm; Comprehensive Development Solution: Ideal for building and prototyping with the ATmega128 AVR microcontroller, this development board is a must-have for enthusiasts and professionals working on AVR based projects. ISP Programming Support: Equipped with an ISP (In-System Programming) interface, making it simple to upload code and firmware updates directly to the microcontroller, enhancing the development experience. Color: Blue Material: Plastic+Metal Package Contents: 1* AVR Single-chip System Board Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.