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They surely can as long the cable is correctly terminated. The more interesting question is however, if the data can be received correctly at the other end. "Long distance" cable drivers are partly using preemphasis to precompensate for the cable losses, also the ability of a dedicated LVDS receiver to decode attenuated signals has been improved with some types.
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Valid point(s). The upside here is that I can still change the spec of the product. I.e. looking at a page like
http://www.interfacebus.com/design_connector_lvds.html I notice that they figure that the maximum length for 32Mbps seems to be something like 70m.
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Did you try a test setup with 100m CAT5 cable? The nominal CAT5 - CAT7 attenuation is 13 dB/100m @ 16 MHz and 18 dB @ 32 MHz, making it unlikely to operate a 32 MBPS LVDS link successfully without additional signal gain and an equalizer compensating the cable loss.
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Pondering... 32Mbps means a maximum line-toggling rate of 16MHz block-wave (1010 pattern). So the line attenuation I need to consider most likely is 13dB/100m as opposed to 18dB. In my case it probably is admissible to simply connect the FPGAs directly (with external 1ns delay-150V clamp surge protector) and then determine the specs afterward by measuring the results. If it is 100m, it's fine, if it's 50m it's still ok, but most likely it will be somewhere around 70m. Except for possibly some extra meters, using extra external buffers does not seem to be to buying me extra reliability/advantages (keep in mind: I don't care what breaks, I only care about the (un)likelihood that something breaks).
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