Symmetricom S200 Teardown/upgrade to S250

[robertps88]

Did you manage to solve this, mine is doing the exact same thing, tried clean cf, and dd ed ones, serial is nothing, the rxd indicator on my serial to usb adapter is blinkinf though, i am trying another thing which is the RAM, maybe it failed during moving the boot files from cf to ram. But finding those ddr1 is not easy. Any thoughts anyone?

[Astralix]

The unit has arrived at the new location, in a box with lots of other network equipment. But construction work is still in progress, so no chance to disassemble the thing and poke around. I also tried to get a second unit, but either none available that fits the one I have or at ridiculous prices, at least for a unit that will get disassembled and analyzed.

So in w few weeks, when the lab is up and running, I'll poke into it.

[drhex]

A chap called Alex Forencich (not sure if he's on here) apparently managed to patch the firmware of the GPS module to work around the week overflow. I found the attached .sx (just remove .hex extension) which I can open in Ghidra as Motorola HC12 file. This is where my knowledge ends though, analysis doesn't really give me things to try - anybody here wiser on HC12 and willing to have a look? May be good enough to inject the modified file into the upgrade package linked in the thread above to get it to install...

[Astralix]

Oh, nice one! That would fix the GPS boards. Too late for me as I bought two replacements (one was stolen but never compensated, because it was deposited before and not behind the front door. Thanks DPD!)
However flashing the HC12 by hand and then having a replacement board is also nice, or just using it for something different.

[drhex]

Hmmm, there even is a flash tool. Wondering if this is for the main board though as there are references to DCF77 in what I linked earlier.

[drhex]

Strangely, mine locks on GPS without any patching?

[drhex]

But not consistently, falls back to NTP from time to time. Seems to be related to the number of satellites it finds.

[ATK]

I've been following this thread for a while, and just ended up getting an S250 with the Rubidium clock from the factory. It was sold as for parts since it was hanging on OS load. I was expecting to find an X72 lamp clock inside of it, but instead it has an SA.33m MAC (!). An interesting note is that even without the OS, the rubidium seems to free-run just fine. The PLL lock diagnostic light on the motherboard comes on (but does not if powered up without the SA.33m plugged in), and I get a very stable 10MHz out. I've not tried any disciplining without an OS, but I'd expect that not to work.

I'm quite happy with all of that, but am curious if anyone has an image for a CF card for a unit this late. The motherboard is an 87-6107R-1 Rev. G. The SA.33m is on a carrier PCB with a P/N of 066-00338-000. Rev. D.

I need to buy a CF card now, but am curious about getting it to boot from a SATA drive. There is a video header on this motherboard, so I may investigate that as well.

[drhex]

For anyone adding the rubidium oscillator to a S350: Jumper J3 needs to be in else it won't be recognized. I have a few adapter boards in case someone wants some - need a bit of work with a file to make the screw holes fit properly as my guesswork was slightly off. Work well otherwise.
Also caved in and bought a Heol module to get GPS working - works well in Survey and Dynamic but shows no satellites in position hold. Hope they can fix that.

[richcj10]

For anyone adding the rubidium oscillator to a S350: Jumper J3 needs to be in else it won't be recognized. I have a few adapter boards in case someone wants some - need a bit of work with a file to make the screw holes fit properly as my guesswork was slightly off. Work well otherwise.
Also caved in and bought a Heol module to get GPS working - works well in Survey and Dynamic but shows no satellites in position hold. Hope they can fix that.

What adapter boards do you have?

Has anyone loaded linux on this and used as that? I have a OXCO mod on my S250.