OpenGD77

I'm getting a Baofeng DM1801 and want to have the option to reinstalled the official firmware later. I read the following in the FAQ

Q. If I install this firmware can I return to the official firmware
A. Yes. But only if you backup the Flash, EEPROM and MCU ROM data, using the Open GD77CPS after installing the firmware, so the Flash memory can be restored prior to reinstalling the official firmware.

Does this mean I install the open source firmware and then save the Flash, EEPROM and MCU Rom Data afterward. How do I do that exactly? It's hard for me to understand how you can save the official firmware if it's already been over written by the open source firmware.

I'm sure I am misunderstanding what I am reading in the FAQ. Can someone point me in the right direction?

Thanks,
73,
Steve_WB8GRS

Hi Steve

Once the OpenGD77 firmware is installed, it can backup the whole of the MCU program.
Specifically, it can backup the bootloader and also the hardware lock bytes stored in the top of the MCU program memory.

FYI.
For some crazy reason both the bootloader and the official application look at these hardware lock bytes and if they don't match the serial number of the radio, the bootloader won't update the radio again, and the official firmware won't run.
Whoever developed this hardware lock bytes idea is a complete idiot, because if those bytes get accidental changed then the radio can get bricked.
And the official firmware has a habit of bricking the radio when people upgrade and then downgrade a few times.

I've actually had to make a patched version of the bootloader, that several people have had to program into their radio using a programmer dongle, because the official firmware had bricked their radio.


Anyway, after you've installed the OpenGD77, if you backup everything. Then even if you completely erased every chip inside the radio, MCU, Flash and EEPROM, you could restore the radio again
Albeit to restore the MCU involves connecting a programmer dongle inside the radio, and the chances of needing to restore the MCU using a programmer are about 1 in a million.

Thanks Roger! I did save everything, but I don't think I'll be going back after using Open GD77
73,
Steve_WB8GRS

Hi Steve

No worries.

There are a few things that are currently not supported e.g. SMS, and some that will never be supported e.g. Encryption.

So for people who want / need those features, they'll need to go back to the official firmware, and probably should never have loaded the OpenGD77 firmware in the first place

So is it possible to flash the patched bootloader without opening up the radio if it's not bricked?
That could prevent the radio from becoming bricked in the first place.

Just a thought.

Patching the bootloaxer would be possible but is high risk, because a patch installation failure results in a bricked radio

I put back one of my radios to the stock firmware without backing up these registers. Apparently there was no harm since I was able to boot the radio normally after that. Was I lucky or may be the latest stock firmware does not do this check anymore?
Thanks.

W1CY wrote: ↑

Fri Aug 28, 2020 4:12 am

I put back one of my radios to the stock firmware without backing up these registers. Apparently there was no harm since I was able to boot the radio normally after that. Was I lucky or may be the latest stock firmware does not do this check anymore?
Thanks.

It seems to be a bit random. One our two people seemed to have problems going back to the official firmware, and then trying to go back to the OpenGD77
You may find you are now stuck with the official firmware.

VK3KYY wrote: ↑

Fri Aug 28, 2020 10:47 am

W1CY wrote: ↑

Fri Aug 28, 2020 4:12 am

I put back one of my radios to the stock firmware without backing up these registers. Apparently there was no harm since I was able to boot the radio normally after that. Was I lucky or may be the latest stock firmware does not do this check anymore?
Thanks.

It seems to be a bit random. One our two people seemed to have problems going back to the official firmware, and then trying to go back to the OpenGD77
You may find you are now stuck with the official firmware.

I guess I got lucky. I returned it to the OPENGD77 and everything works. May be the latest stock version saved me. Anyway, I will now backup everything. Thanks for this firmware, I am always updating it to the latest development version in github. Cheers.

OK.

If you have managed to reload the OpenGD77 firmware, your bootloader / hardware protection data must still be OK.