PlanetZ forums - scopeusers.com

Yesterday when I tried to reconnect my A16U to my Scope board, I could not for the life of me get z-link to sync.
The only sign of life I got was from the B-bus on the A16U. The red "LED" on the z-lin connection in the samplerate-menu would flicker, indicating some sync problem.
While I could use whatever bus I wanted on the Scope board, only the B-bus on my A16U would work. A-bus was completely dead.

Thing is, I think this happened because I accidentally managed to insert the firewire cable up-side-down (sic!) into the Scope board. I was fumbling in the dark behind there.
I noticed the I/O-plate was somewhat displaced, especially the z-link connectors, so I fixed that, but to no avail.

Do you think I managed to burn up my A16U? I have no way to test this as I only have one.

did you try the cable that worked on the side that didn't? perhaps it's the cable or the connector on the A16 which is damaged, but...

that cable carries power. this doesn't sound good....

Yeah, I tried both cables including an extra I had laying around.

Only B-connector on A16U has any indication on the Scope board, be it A- or B-connector.

I am not sure whether the A16U powers the Z-link, but the Scope board sure does with the 12V connector, so I might have fried something in the A16U.

It still baffles me how I managed to connect them up-side-down :

yeah, crazy....

voidar wrote: I am not sure whether the A16U powers the Z-link, but the Scope board sure does with the 12V connector, so I might have fried something in the A16U.

the A16U won't supply power on the pins. only the card does. that's why you will damage 2 Lunas by connecting them via Z-Link.
a Luna2496 (the little brother of the A16U) isn't even able to inject power since the Z-Link cable is the only connection to it (apart from analog I/O). it has no power input other than the Z-Link supplied power.
I'm kinda sure the A16U ignores supplied power from the card, but only on the correct pins. if you indeed managed to reverse the IEEE1394 plug on the card there is a certain possibility you supplied power to the wrong pins and fried something.

-greetings, markus-

voidar wrote:... It still baffles me how I managed to connect them up-side-down :

well, it's a piece of sh*t from the design point of view
I've seen them doing it with external disk drives in the office and I'm almost certain that I once managed to plug it in the wrong way, too. Actually I was surprised how smooth it went in

anyway, there's up to 1 Ampere of current on the supply line and that is a lot
I would assume the engineers took care of this when connector specs were released, but obviusly that's not the case.
Even inserting the connector in the proper direction still has the capability to fry what's on the other end - in my case at least 3 disk controllers.
You could smell it and you could see the traces of smoke on the circuit board
hot pluggin has a completely new meaning for me since then...

cheers, Tom

Thanks for the enlightenment on the design.

I have yet to open the A16U, but I would presume it would be difficult to repair on a component level.

The irony is I think I hooked it up with nothing turned on .

voidar wrote:The irony is I think I hooked it up with nothing turned on .

well, did you physically switch off the psu?
if not, the board is powered, and some power is also distributed to certain components. ever wondered why (especially) lan cards have their link leds lit though your pc was shut down?
I kinda doubt that the zlink port of a luna or z-link blade is still powered in the power-off" state, though, since I can tell that a luna expansion doesn't seem to be powered up at least...

mhh, whatever you did, it's miraculous...

-greetings, markus-

Oh, I did eventually power it on, just took me some time to notice something wasn't functioning ..