Icsp pins arduino mega pinout serial#

The options there are all parts with less of all memory types. This will make the Uno R4 board accept any AVR that is pin compatible with 328P, make that board not only a electronics prototyping platform but also a more powerful AVR rescuing and programming tool. I don't know if you'd want it hardwired into the board (I'd prefer not, just to keep the SPI bus cleaner electrically) or just have a set of headers that a user could connect via 2-pin jumpers, or via a short 4-pin cable (Reset, MOSI, MISO, SCK) if routing between the 16U2 header and the ICSP header was an issue. There was another topic recently describing using the USB/Serial 16U2 to do ICSP programming of the 328P and 2560, so it's certainly possible. The 16U2 can also output its 16MHz clock signal (using fuse settings) to the 328P, eliminating the crystal attached to the 328P. The LM358 can be eliminated by leveraging some more pins of the 16U2. For Mega2560 boards with this design, an adventurous user can desolder the 2560 chip and add a ZIF socket to make it a similar tool to fix any chips pin compatible with the 2560 chip.

Icsp pins arduino mega pinout serial#

The 16U2 still functions like a USB to Serial adapter during normal operation so that existing sketches need not to be changed. During normal operation the 16U2 will tri-state its ICSP pins to prevent it from interfering with the 328P.

When programming is required the 16U2 will act like an ICSP programmer and reprogram the 328P over SPI ICSP. In this mode of operation, take the Uno R4 as an example, the 328P will not need a special bootloader. Since we already have some way to use an Arduino, especially the Leonardo, as an ISP, is it possible to incorporate that code into the ATmega16U2 chip and make the 16U2 reprogram the 328P (Uno R4) or 2560 (Mega2560 R4) using ICSP instead of using the serial bootloader?