@hli:
"So you want to spend considerable time to implement a logic analyzer in a FPGA,"
Yes !!!
"and then want to spend even more time implementing the proper PC interface GUI to use it?"
No, there are reasonable existing programs for this, they just need to be fed with proper data.
"What is it that you don't like at the existing logic analyzers?"
The one that I can afford are more or less garbage, the one that are working properly, I can't afford
.
"What are your targets in respect to sample rate, channels, sample depth, triggering and decoding capabilities?"
At least 100MHz in state mode, 500MHz in sample mode, 36 single ended channels, 18 LVDS channels because it's the $current year, sane RLE implementation, sampling gating (bonus gating on pattern), trigger on edge, trigger on pattern, adjustable number of trigger occurrences, continuous streaming to the PC at (as close as possible to USB3) max speed using the on-device external memory for buffering of bursts.
Really sweet cherries on the top: simultaneous sampling/state acquisition (that is synchronized sampling in state mode using the external clock as synchronizer for the sampling clock), advanced protocol decoding(HDMI, USB, Ethernet), pattern generator synchronized with the internal or external clock.
"I would encourage you to look at e.g. the
Digital Discovery - it comes with a Spartan 6, 2GBit of DDR2 memory, and its properly routed to allow sample rates of up to 800MHz. And it comes with quite some capabilities in terms of triggering an decoding (e.g. complex triggers, or triggering on decoded protocols)."
I was encouraged to look on it some while ago when I was looking for an LA, I've looked carefully on it, at it's price and capabilities, and IMHO it's a rotating overpriced turd, that was created specially to gouge students and universities of a lot of cash (the prices in Germany are outrageous) for mandatory projects, the obsolete FPGA platform, the miserable architecture and design, not to mention the useless software, convinced me that along with the brother turd, the Analog discovery, it's a project to teach the students to discover that 99% of everything it's crap (Sturgeon was an optimist) and they just have dropped around 500EUR for a piece of it. At least they can proudly show the 56EUR "high-speed" adapter, it could be that there is written with very small letters: "suckeeers"
. Also not in a 1000yrs this thing will sample reliable anything close to 800MHz, ever. And the linked review was kind of lukewarm, really the guy was mentioning sniffing I2C and UARTS ?!?! with this thing, 200+ EUR for it ?!?!, well at lest I've seen that they dropped the price for the "high-speed" adapter, just 46EUR
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@asmi Good to know, maybe Cypress will drop the prices for FX3, personally fact that I can't control the USB personality and firmware and make it a USB class device, the need of special drivers and libraries instead of using the OS optimized class drivers and no libraries and DLLs, turned me from buying an otherwise promising board. I may be biased here, because I know very well the FX3, but even when trying to be as impartial as possible, I don't see any kind of advantage of this chip, maybe it's cheaper. Also FTDI is on my black list for the USB-serial fake chips disaster, they even had the gale to submit a Linux patch to destroy the chips as well !!!
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@ace1903 Actually I've found the Artix board of the same seller:
https://www.ebay.com/itm/Cypress-CYUSB3014-USB-3-0-Development-Board-with-Xilinx-Artix7-FPGA-XC7A35T/173113636330 and if by the end of the week I don't get a better suggestion I may give it a try.
Thanks anyway for the suggestion, this was welcome and what I've asked for.
Best regards and thanks for all the advices, they are welcome but some may be a bit harsh criticized,
all the critics are for the object and NEVER to the person. Cheers,
DC1MC