4 ms·
With some basic SERDES knowledge I wonder what could be done in 2022, now that we have cheap FPGAs. Ronja is limited in that it piggybacks on 10BASE-T Ethernet,
by RicoElectrico 5y ago
With some basic SERDES knowledge I wonder what could be done in 2022, now that we have cheap FPGAs. Ronja is limited in that it piggybacks on 10BASE-T Ethernet, which in turn makes in simpler. It wouldn't be easy to analogously piggyback on 100BASE-T due to PAM-3 transmission. An FPGA would allow for a bespoke PHY/MAC to be implemented in lieu of Ethernet.
There are many techniques for pushing bits into a wire faster, like CTLE, DFE, pre-emphasis, to name a few. Probably the best starting point would be Behzad Razavi's "Design of Integrated Circuits For Optical Communications".
For starters, the LED driver could use current switching with some idle current (pre-bias) in "0" state to achieve more bandwidth.
- wolrah 5y agoAs I see it, RONJA's nature as a hack of ethernet was one of its benefits, it could be integrated with ordinary ethernet gear. I think if one was to try to develop a followup, basing it on one of the fiber variants of ethernet seems natural enough considering the idea is more or less fiber without the fiber. In theory up to 25G ethernet could be attempted with something like this, anything bigger than that uses multiple lanes or multilevel encoding, but obviously in the real world the practical limit for something that could be built at a DIY level is maybe gigabit realm.
- RF_Savage 5y agoYep. Could see a low cost FPGA with a being used for a new, more advanced ome with better linecoding, FEC and DSP on the receive side. And all that cheaper than the original RONJA was back in the day.
- Kliment 5y agoThe modern version of this is http://www.koruza.net/features/ http://www.koruza.net/features/ which piggybacks on fiber transceivers.