Port stacking (multiple devices)

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Port stacking (multiple devices)

Postby lathe26 » Mon Jul 06, 2015 1:30 am

It looks the trigger/clock thru-holes could be used to synchronize multiple Sniffers to collect data from even more channel. One reason would be go higher than 32 channels. Another reason would be use 4 Sniffers with only 8 channels each to get 32 channels but with greater sample depth.

My questions are:
1. Are people doing this already?
2. Does the software support multiple Sniffers at the same time?
3. (Advanced feature) Support trigger testing across multiple Sniffers. This means having each Sniffers trigger-out signal only be asserted when the pattern is matched and deasserted if the pattern later goes away. This way multiple trigger-out signals could be AND'ed together to produce a single master trigger that gets wired to all of the trigger-in. For example, there could be 2 Sniffer devices where one watches a 32bit address/data bus and the other device watches the other bus signals to know when a specific address is being asserted (and not when similar data is on the bus).
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Re: Port stacking (multiple devices)

Postby arhi » Tue Oct 13, 2015 10:15 am

lathe26 wrote:1. Are people doing this already?

I used to link 2 of them together, so yes

lathe26 wrote:2. Does the software support multiple Sniffers at the same time?

nope, but sniffer is a simple serial port from the pc perspective so you can run multiple clients and connect them to different ports as a workaround

lathe26 wrote:3. (Advanced feature) Support trigger testing across multiple Sniffers.

I was experimenting with some dual trigger mode so first time trigger fires obls1 captures, second time it triggers the obls2 triggers .. that works ok and is not hard to configure since triggering in obls is pretty good but what I didn't manage to get to work is just simple chain, to get obls1 to trigger obls2 when it hits end of buffer so that obls2 can continue... it would require small change in firmware to do so (or maybe possible already only I don't know how) .. anyhow I got a big hp LA in the meantime so obls is not as useful as it once was especially as it's dead project imo (no, not mature, dead, if you have known bugs and no git update in 4 years, if most of tools are broken for more then a year it's called dead not mature)
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