- Hi everybody. Thank you for the efforts invested in troubleshooting problems with MEGA 2560 bootloader. If it helps I will document my solution to above mentioned anomalities. My problems started when arduino ide (v1.5) was not able to upload mega 2560 board every time. Sometimes it did hang up without any notice and because of that I entered the world of MEGA 2560 bootloader reflashing. Luckily I have two usbasp programmers (one betemcu board other hobby king one). Arduino ide uploaded bootstrap with usbasp ok but verification failed as mentioned in this thred. Strange thing was that board was still operational (it was loaded with two bootstraps - one on right place 3e000 and second on 1e000). If fuses are ok the board should work. I programmed it with avrdude , khazama and extreme burner (all with same results).
The problem is with firmware in usbasp programers - mine was version 1.02 on both programmers (windows XP control panel system hardware libusb usbasp driver properties hardware id) which does not properly support intel hex records 03 and 04 type (addressing over 64KB). When I reflash usbasp programmer with version 1.04 (from official usbasp site) arduino ide was abble to burn new bootloader using usbasp withouth any error.
It still leaves open the problem of occasional timeouts during board upload from arduino ide but I hope it answers the misteries connected with mega 2560 bootloader reflashing.
