[Irving Moy]

It’s great to hear that the v2.16 firmware fixes all those issues.
Thanks for all the help with the DPS, I really do appreciate it.
I just joined DSLReports. How do I find you or do I post my DLSReports login name?

[Irving Moy]

Looking through the parts list in the Service Manual, I found the One Time Programmable EPROM (QU17) that probably holds the DPS’s operating system, and 2 Flash memory chips (RU1 & RU2) that probably holds the replaceable firmware. The EPROM is socketed but the Flash chips are surface mounted with 48 tiny leads. The EPROM can be replaced but it has to be first programmed with the DPS operating system. The Flash chips look like they need SMT experience to replace. The cheapest and easiest option is to spend $100-$150 on another used DPS 475 and hope it keeps working.

[Irving Moy]

OK. I’ll see if I still have RS-232 straight through cables somewhere, but I’ll probably have to order one. It’ll be cheaper than buying the raw cable & connectors and wiring one myself.

There’s nothing in the Service Manual about failsafe recovery. I opened the DPS 475 when it failed but I don’t remember seeing any DIP switches, unless they are under the Audio Synchronizer Module’s circuit board. I also tried to read the schematics in the PDF version of the Service Manual, but the schematics are too blurry. I can’t make out any of the smaller lettering.

[Irving Moy]

I know about the DSLReports site and its forums but I’m not a member.
I’m on Reddit, Slack and Discord but I don’t know how popular those services are in the digital video and video production communities.

[Irving Moy]

Mmm… I don’t see any contact info in your Creative COW profile. If I login by using my LinkedIn account, will that allow you to contact me offline?

[Irving Moy]

I was using an old serial cable that had DB9 connectors on both ends, so it probably was a null modem cable used to transfer data between computers before Ethernet networks became the norm. Adding the null modem adapter unswapped the TX and RX lines.

The upside to the DPS failing is that it caused me to do a more detailed search for frame synchs for use in a VHS digitization workflow. I found the Ensemble Designs BrightEye series. The BrightEye 3’s description explicitly mentions its use with VHS decks and the BrightEye 75 has embedded audio, which would make it a drop-in replacement for my DPS. I asked the manufacturer if the BrightEye 75 is compatible with VHS decks and they said yes, it would be better than the BrightEye 3.

[Irving Moy]

Thanks for the tip! I tried it several times and still got the “No loadable firmware.” message on the front panel display. Then I tried the other Power-Up Keys as described in the Service Manual. The BYPASS button did trigger the self-test but the MEMORY and KEYER buttons did not trigger their power-up functions. On the fourth or fifth cycle of trying all the power-up buttons, the ENTER button did trigger the “Download firmware.” message. I ran the firmware uploader on the PC but it still could not connect to the DPS.

This time I remembered to check if the serial cable needed a null modem, so I dug out the RS-232 tester and sure enough, the RX line was active instead of the TX line. I plugged in a null modem adapter and the uploader program was able to connect. But the upload failed and the DPS front panel display showed 0% loaded because there was not enough space in memory for any uploads.

Since holding the KEYER or MEMORY buttons at power-up did not trigger the delete firmware or wipe memory functions, I don’t see a way to make room in the EPROM for an upload. So it still looks like there is a problem with correctly accessing the EPROM.

[Irving Moy]

Thanks for all the information!

I’m glad to hear that your question about upgrading has been answered.

I did find the v2.15 and v2.16 firmware, plus the Windows uploader program. I tried to upload the firmware to the DPS but the computer could not connect to the DPS. That was disappointing but not surprising since the DPS could not load the firmware from the EPROM. That means the DPS had no operating system running in RAM that could respond to the uploader program.

I suspect that either the EPROM has failed or the circuitry that reads the EPROM has failed. I read on another forum that there is no one left that services these frame syncs. Even if I manage to replace the EPROM, I have no reasonable way to load the firmware onto the new EPROM, so the DPS is effectively dead.

I see other used DPS 475 units for sale on eBay but I am hesitant to spend more money on another unit that may also suddenly fail. I’m instead thinking about renting an AJA FS1 since the company is alive and well and the FS1 is still a current, supported model. I’ve been impressed by all the AJA products I’ve used so I may eventually take the plunge and outright buy an FS1.

[Irving Moy]

Hi Jan,

I also have a DPS 475 frame sync/TBC that I use to digitize VHS.
I turned it on today and I get this message in the display:

DPS Boot EPROM rev.G
No loadable firmware.

I bought the 475 used, so I do not have a copy of the firmware to re-flash the firmware.
May I ask where you found the firmware, since Leitch was purchased by Harris and they don’t seem to be supporting the 475?
I might be able to answer your questions about options since I will be probably upload the firmware more than once to see if there is an issue with the EPROM.

Thanks!