Doremi / Dolphin DCI 1.0 - Secure Clock lost, still plays encrypted content

[Carsten Kurz]

A colleague contacted me about his early generation Doremi servers (DCP2000), connected to their series 1 projectors. Apparently, and as he explained, this server/dolphin board did not receive maintenance for a long time and thus the battery ran dry a couple of years ago already (it was recently replaced with a new battery).

This issue turns up in the Dolby Log Analyser as 'Error - the Dolphin board RTC time has been lost', and within Device Manager as 'Secured Clock Status : broken'.

Yet this machine plays encrypted content many years since this happened. I know there are differences between Dolphin 1.0 and 1.2 (basically, the addon SBC security manager, and the board molding), but has someone experienced the same with a Dolphin 1.0? How can this board decide about KDM validity if the secure clock has been lost? Will it just use system clock instead? The dolphin mounting bracket (Twin-HD-SDI+GPIO/DVI connector) and Logfile analysis clearly indicates it as a Dolphin 1.0, not Dolphin rev B. Software is 2.6.4.

[Marcel Birgelen]

Has your colleague ever tried to play a DCP with a KDM that's not yet valid or has since expired? Would be interesting to see what happens.

[John Thomas]

Reinstalling 2.6.4 may be a relatively harmless thing to try, or swapping the board with another DCP2000 to see if the problem stays or moves.

I don't have a (working) machine with a Dolphin in front of me to help with specifics, but I would peruse /doremi/log to see if there is any obvious indication of the RTC clock actually still working. Seems like it has to be.

While it makes sense from a technician's standpoint to want to get the thing into an expected, 100% good or 100% failed state, if the issue is with the Dolphin board I fear the latter is more likely.

[Sean McKinnon]

I am not an expert on series 1 or older doremi versions but I suspect he is running a non DCI compliant version of the software/firmware and if he upgrades to a DCI complaint version he will not be able to play encrypted content at all.

[Carsten Kurz]

Basically, they are doing fine with these so far. They are now thinking about a safe but low cost way into the future. I think with 2.6.4, they are safe SMPTE DCP wise. They are probably hesitating to perform any software upgrade because they fear it could break their working set of servers. They somehow digged up a Christie IMB-S2 for one of their Christie S2 projectors, but, given the failure rate of those, they are not really a future-proof replacement for these Dolphin 1.0 boards. The certs for these boards will probably expire in late 2025 as for all Dolphin boards. That's still 4 years, and they will probably have other options until then (especially since their Series-1 projectors will likely give up earlier).

[Jim Cassedy]

Ironically, on Tuesday of this week, I was at one of the still closed screening rooms
I sometimes work at to go throughall of their equipment in preparation for them
re-opening some time in the near future. They too have an older DoreMi DCP-2000
running software 2.8.26-0, and connected to a Series 1 NEC projector. They are
getting two error messages about the secure clock battery, One of which you
see below, and a 2nd one which said that the secure clock battery was
something like over 380 days past its' replacement date. At first I thought
they were in big trouble because it wouldn't play an encrypted test file I'd
made for them using DCP-O-Matic, but I later realized that this was due to
an error on my part in rendering the DCP files. On 2nd try, it not only played
the test file I made, but also the one that's available on the Dolby™ website.
I've been told that they were getting that secure clock battery warning even
before they shut down for the Coronapacoplyse, but ignored it. I've informed
the owners of their options and the potential risks of their server turning into
an expensive boat-anchor if the battery issue isn't dealt with soon.

DoreMI_ErrorMsg.jpg

I did have Dolby analyze the log file, and they said that the the 'secure battery alarm'
is triggered only by the passage of time since the battery was last changed, & that the
the DoReMi does not actually measure the battery voltage or condition. They also
recommended upgrading this DoReMi to 21.04n firmware & to software version 2.8.30.

> I'm pretty sure this server has one of the older Dolfin boards with a replaceable battery
because I have vague memories of replacing it when they first got this server around
2011 or 2012. They got it used and I recall it still had some inventory asset barcode tags
from the "Deluxe-Technicolor QC Department" inside.

[Carsten Kurz]

It's true that there is a time-based only software alert on these systems. However, in the case of my colleague, they know that the battery was over time by many years. And their log report says 'RTC/secure clock lost'. I recently changed a cell on a Dolphin 1.0 more or less exactly after the 5 year software warning came up. The cell voltage was around 2.98 volts and that is probably still enough for a couple of more years (although probably no one knows exactly at what voltage the Dolphins lose their cert). I would assume that 7-8 years is quite possible, however, as the cell only costs a few cent, one should not risc it. Especially, as I think is true, that Dolby will still reserialise Dolphin 1.2 boards, but NOT Dolphin 1.0 boards. Therefore I also recommend swapping the Dolphin battery with the server running. Which is a bit of a delicate procedure, but only 'a bit'. With some precautions, it can be done safely.