SerialUploader

Serial upload sketch for Arduino.

This sketch turns your Arduino into a standalone serial programmer.

The only protocol supported is stk500v1 (a.k.a. "arduino" in the IDE's boards.txt), with support for page sizes greater than 128kb; this covers atmega2560/2561 boards with the megacore bootloaders installed.

The IDE's default bootloader for the Arduino Mega uses the wiring (a.k.a. stk500v2) protocol, and is not supported.

How to use:

1. Prepare a programmer board with an SD card
2. Set up preferences in SerialUploader.h
3. Upload the SerialUploader.ino sketch to your programmer board
4. Compile the sketch you want to program (e.g. using the Arduino IDE) (Remember to adjust the IDE board settings for the target board!)
5. Locate the generated .ino.hex file on your file system, and copy it to the SD card
6. Move the SD card over to the programmer board
7. Connect the programmer board to the target board:
   • programmer -> target
   • Vin -> Vin
   • Gnd -> Gnd
   • PIN_RESET -> Rst (or PIN_DTR -> DTR if so configured in SerialUploader.h)
   • SERIAL_TARGET Rx pin -> target's Tx pin
   • SERIAL_TARGET Tx pin -> target's Rx pin
8. Reset the programmer to start the upload sketch

The built-in led on the programmer will show:

• sequences of 2 quick blinks if the upload succeeded
• sequences of 5 quick blinks if the upload failed While the upload is in progress the LED will reflect Serial communication between the boards.

The sketch will try standard upload speeds down from 115200 bps. This works well, but as an alternative you can add a boards.txt file on the SD card: the sketch will find the first occurence of "upload.speed=" in the file, and will use the upload speed specified there. Sample file: # Upload speed for serial uploader optibootm32.upload.speed=38400

The sketch appends to an upload.log file on the SD card: you can check that on the computer to see what happened.

Tested programmers:

• mega2560 clone, Serial1, RST
• Uno, Serial, RST
• Pro mini 5V 16MHz, Serial, RST and soft DTR

Tested targets:

• Uno target board, optiboot, 115200
• Pro mini 5V 8MHz, minicore, 38400, RST and soft DTR
• Pro mini 5V 16MHz, MiniCore, 115200, RST
• ATMega2560 pro mini (clone), MegaCore, 115200, RST

Credits:

• https://github.com/robokoding/STK500
• https://github.com/Optiboot/optiboot
• https://github.com/MCUdude/MegaCore
• https://github.com/nickgammon/arduino_sketches