@6v6gt Thanks: Resetting the WDT to 16ms explains my problem. I use an 8MHz version of the standard bootloader on a custom board. I had a quick look at optiboot and I will probably need to make my own version of it: that needs more investigation.
@6v6gt Thanks: Resetting the WDT to 16ms explains my problem. I use an 8MHz version of the standard bootloader on a custom board. I had a quick look at optiboot and I will probably need to make my own version of it: that needs more investigation.