#apertus IRC Channel Logs

off to bed now ... have a good one everyone!

I'm pretty confident those active converters/extenders will work but not sure how they help except for permitting longer cable ranges

or targeting namibj

jhlink: Significantly faster than what the Axiom can/could push out via ethernet.

I'd really like to know what chips they use for the conversion

Bertl: if they'd not be that expensive I'd like to use one for analysis. Maybe one can get a broken cable on ebay? I understand they fake a couple hubs, likely to accumulate the allowed per-hub delay to get enough for whatever optical PHY they use for it.

usb3 timing is evil.

anyway, what do they cost?

If the Axiom Beta runs storage of an SD card, and the maximum R/W times are less than 1 Gbits, then the bottle neck will be flash memory, not the communication protocol

and there could be two of those plugins in use at the same time

Probably wrong, but open to corrections! :D

and the maximum realistic data rate there is about 800MBit/s

Bertl: corning? 150 for 10 to 550 for 50

Goot it. :)

Bertl: you mixed them up. 150 EUR for 10m, 550 EUR for 50m..... Honestly, I wish tey'd be affordable, because then I could easily test...

However, now there is food on the table. Cya

@ethernet, in theory yes, but we didn't test that yet

still it's only 1Gbit at most

yes, AFAIK they can be used from the fabric

10g ethernet in a small package would be nice

the design uses a zynq with gtps and a TLK10031

the price with 20 EUR is high but not that high

Bertl: a gigabit is a gigabit ;).... There are reasons why I considered asking trenz about solding a 10ghz trensceiver version, where the only real difference would be the higher specs and a metal lid over the flip-chip, in one of their micro modules. It would have been smaller than the zynq, with 3 high-density connectors on the bottom. I decided against and went for a genesys 2, because of the higher

felix_: so let it have no jumbo support. I don't care about the measly increase in datarate, just about the lower scheduling overhead due to lower packet per second counts.

well, we have two plugin slots with a total of 12 LVDS pairs capable of at least 1Gbit/s each

basically TE0745-02-30-2IA with the FB part swapped out for a FF part. Nice and compact, no more than 4/6 layers should be needed on the host. But as said, I didn't go for it, and I gotta ask the guy from Kron Technologies I met @camp for telling me which sub-500$ fpga board he mentioned that could handle 10G ethernet on SFP+.

(because that's not sub 500$ :)

packets appropiately.

well, for raw unidirectional ethernet frames, you can just drop the received data

you might also make it 10G/1G bidirectional

Bertl: it's about whether the optics themselves play with this, considering that you'd want to skip the useless fibers to stay within the cheap/light 12-fiber cables.

the sensor can do 1 to 64 LVDS pairs for data

I know. I meant per channel. If I use it with the genesys 2, I'd try for 64.

and at 600MHz you are probably fine for some distance

50cm is a lot for 67 LVDS pairs

Bertl: 15 might suffice if I'd push it, assuming it's for the 400mm f/2 design from https://www.telescope-optics.net/field_flattener.htm example 1 deign point 7 (the 7is circled in).

This is already at the edge of the sensor, btw., with 2 degree off-axis (= 4 degree diagonal FOV).

nn