05-31-2015, 10:30 PM
Hi, recently I installed the firmware 7820 and connective kit crashs. Is it possible downgrade the firmware to 6975? I tryed to install it but when its done the prime keep running the 7820 =/.
Thank you
Thank you
05-31-2015, 10:30 PM
12-18-2016, 08:26 AM
I had the same question today, and found a way to do it. The trick is to use the recovery mode to install the firmware.
Basically you follow instructions 1-4 from here:
http://h30434.www3.hp.com/t5/Calculators...-p/4391146
Then at step 5, you can use the connectivity kit instead of usbtool (using the connectivity kit I think might be safer).
Before you start the connectivity kit, make sure that you have the right firmware version that you want to downgrade to in the folder `C:\Users\yourUserName\Documents\HP Connectivity Kit\Firmware`. Just download the version you want from http://ftp.ftp.hp.com/pub/calculators/Prime/Archive/ and unpack it to that folder (delete everything else in that folder first).
Basically you follow instructions 1-4 from here:
http://h30434.www3.hp.com/t5/Calculators...-p/4391146
Then at step 5, you can use the connectivity kit instead of usbtool (using the connectivity kit I think might be safer).
Before you start the connectivity kit, make sure that you have the right firmware version that you want to downgrade to in the folder `C:\Users\yourUserName\Documents\HP Connectivity Kit\Firmware`. Just download the version you want from http://ftp.ftp.hp.com/pub/calculators/Prime/Archive/ and unpack it to that folder (delete everything else in that folder first).