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Serial digital interface (SDI) is a digital video interface used with the most of professional video cameras. It uses BNC connector and operates at speeds of 3 Gb/s or about, depending on the standard. The more detailed specification can be found in wikipedia. Most of the SDI adapters for FPGA use FMC connectors, like this one. There is no FMC connector on Zybo Z7 board, but it does have multiple PMOD ports. Could they probably substitute? If some simple extra circuitry is required, we maybe could build it on the top of some generic PMOD adapter like this. My major doubts are, would such interface be fast enough? I am not aware at which frequency Zybo PMOD port and the custom circuitry attached to it could operate.

Hi Folks Although the Analog Discovery has fully differential analog (scope) inputs, the Discovery BNC adapter board does NOT! For some reason the negative inputs of both analog channels have been connected to the Analog Discovery ground. Therefore, they form a short circuit between any conductors they are connected to. Why is this important? I just found out the hard way, when I connected the scope leads from the Discovery BNC adapter board to parts of a circuit at very different voltages. I was expecting each channel to measure the differential voltage across each probe. Instead, there was a crack, a flash, and a little jet of molten metal, as the clip on one of my scope probes vaporised! IMO this is a safety hazard, because adding the Discovery BNC adapter board to the Analog Discovery changes its electrical behaviour in a significant way (from differential to single ended) but there is no mention of this in the Discovery BNC adapter board reference manual. Users should be warned in BIG LETTERS about this change in behaviour, perhaps printed on the PCB as well. I was lucky, but providing users with a warning about this could save somebody's life one day. I can see that grounding the negative inputs could make sense, in that it makes the analog inputs behave more like a conventional oscilloscope, where the probe shields are usually returned to Earth. However, if you're going to do this you should at least warn users about what you've done. IMO it would be better to provide 4 sockets for scope probes, with each connected to one of the differential inputs, and all the scope shields returned to Analog Discovery ground. Then the Discovery BNC adapter board could be used for fully differential measurements. You could also provide jumpers to select single ended behaviour instead, by shorting the negative inputs to ground. At least that would give the user a choice about whether to operate as differential or single ended inputs.

I'm trying to configure the Discovery2 with BNC adapter to transmit three different clock-synchronized pulses to three interacting pieces of equipment via the BNC. I'm aiming for precise independent control of waveform, frequency, pulse-width, triggers, etc, all from the same master clock. I need precise pulse timing integrity at the khz level, with minimal degradation over 30ft+ cable distances, hence why we are aiming to use the AWG on the BNC rather than the pattern tool on DIO pins in WaveForms. The BNC Adapter for the Discovery2 is configured with two input and two output ports. Is it possible to reconfigure the input ports as outputs? If not, is it possible to physically convert digital pins (plus grounds) to BNC without signal degradation? What other options might exist for transmitting three output signals with BNC rather than digital pins? Is it possible to link two boards with the same master clock? Or, is it possible to maintain the quality of signal necessary using the digital pins, making all of this a moot point? Assuming it's possible to run three BNC outputs, is it possible to control this from Waveforms (given only two channels of AWG, where we need three), or will we need to write a custom application?

Hypothetical question. According to Discovery2 reference manual (https://reference.digilentinc.com/reference/instrumentation/analog-discovery-2/reference-manual) there is a maximum of 50 volts peak AC input to the oscilloscope leads. If I use my BNC adapter board and set the switch on my probe to 10x setting, could I look at 110 volts AC from the wall outlet without doing damage to my Discovery2? Would it look like eleven volts on the computer screen?

The retired product, PmodCON2 (BNC adapter, http://store.digilentinc.com/pmodcon2-bnc-connectors-retired/), is exactly what I need! Are there any equivalent products, or do I need to solder something myself?

What advantages does the BNC adapter offer to the first generation Analog Discovery?