flasher and passthrough cycle w/ SREG message

[beckdac]

Hi,
I'm trying to use the flasher app with your modified optiboot for over the air flashing of an AVR. When I run the flasher.hex on my atmega328p, I get the SREG message which repeats every few seconds, something like:

SREG: 0x0002, MCUCR: 0x0000 , our addr: sl0

Maybe it is resetting? I run the flasher.hex overtop your modified optiboot boot loader. Scoping the I/O lines to nRF24L01+ I can see typical behavior for the setup. With passthrough.hex running and in minicom, I can delay the reset by pushing characters. Interestingly, the I/O lines to the radio are silent. I suppose I thought I would see them pulse as it tried to send something.

Any thoughts?

• DB

[balrog-kun]

Hi, sorry for the slow response...
That hasn't happened to me, but I can imagine one possible cause: have you compiled the optiboot bootloader and flashed it onto this atmega328p? The thing is that this modified optiboot will reset the board every 4-5 seconds unless the application takes care of disabling the watchdog, and it would result in what you're seeing.

Personally I've only used the modified optiboot on the "remote" atmega, and standard optiboot on the "local" atmega, which runs flasher.hex. As a result I didn't think of disabling the watchdog inside flasher.hex but I'll be sure to modify it and upload the change to github on the next occasion.

Please let me know if you succeed in over-the-air flashing or if you hit any other issue, thanks.