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Page Lari

Downgrade Vivotek (Howto) / IR Not Working (Question)

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Hi everyone, I found this forum while trying to figure out why my Vivotek IP8332 camera suddenly won't illuminate it's IR LED's for any reason.

It did at a previous point, and I thought it had failed after an upgrade to v0401a of the firmware. I tried to downgrade the firmware to earlier versions, including a full reset via the internal button each time! However, the IR LEDs still refused to illuminate, no matter which major version of the firmware I try. I have gone from 0401a down to 0105b with no luck.

I figured I'd come here and ask my question, while at the same time demonstrate how I was able to downgrade the firmware.

There is a "magic number" in the header of the firmware it uses to determine if a firmware can be "upgraded". Someone else had posted here that Vivotek support claimed there were significant differences between major revisions of the firmware and so they didn't want end-users downgrading for whatever reason. I couldn't find any evidence of this, the header for each version are nearly identical, apart from the magic number change, and the size of the firmware changing. So, I decided to change the magic number (which is just literally incremental) and it worked.

If anyone wants to downgrade their firmware you simply need to open the target firmware with a hex editor and change one single byte at offset 31 to any of the following, matching the firmware currently in use on the device.

01xx: 110  (n)
02xx: 111  (o)
03xx: 112 (p)
04xx: 113 (q)

So, if your camera has the 04xx firmware and you wanted to downgrade to anything lower simply edit the firmware file of the target version and change byte 31 (counting from 0) to 113 (q) to match what the script expects for the current firmware.

Example: Original 0401a Firmware:

Example: Original 0301c Firmware:

Example: Edited 0301c Firmware to allow downgrade from 0401a Firmware:

Once the file has been edited then it can be uploaded via the built-in interface under Admin -> Maintenance. One reason I suspected this would work is the upgrade script it runs is the same version, 0101a, across all the various firmwares, so clearly they didn't actually change anything if the same upgrade script is still in use. Of note, the script seems to use the magic number to determine how to display the version number you're "ugrading" to, even if it's a downgrade. This means the upgrade script will show a wonky version number, a mix of the current major version and the minor version for the target firmware. This is just cosmetic though, once the device is downgraded the version shows correctly in the interface as expected.

Hope this helps, and hopefully one of you may know how to re-enable the IR LEDs on this IP8332 camera. No idea why they don't work, but figures the one time I need to use them they no longer function! Ugh!

~Page Lari



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