Honored Contributor
Honored ContributorFirst sorry I missed this post.. I've been juggling a couple of projects, and didn't see your reply.
--- Quote Start --- The Dedicated differential output buffers on side I/O banks support LVDS transmit at up to 840 Mbps. Is that is why you suggest that sending 720p frame is doable in Cyclone III? --- Quote End --- Yes. --- Quote Start --- Apart from that, I'm still a bit confused about I/O pin speed. The fpga specification give the throughput per pin, and not per channel/lane, right? --- Quote End --- Kind of: they are giving you the number per pin pair, which I'm saying is per channel/lane. The HDMI standard uses three data lanes. So they are specifying the data throughput of the system, which uses 3 lanes. --- Quote Start --- Another thing, the throughput that the specification gives depends upon the max frequency the fpga could support, right? --- Quote End --- Yes. --- Quote Start --- That's said, is it possible to calculate the min I/O pins speed I would need for example to use TMDS protocol for a given resolution? --- Quote End --- Yes. But you have to take into count vertical and horizontal blanking times as well as the number of pixels. For each resolution however there is a "Standard" clock rate for the resolution that you can simply mutiply by 10 to get the IO rate. --- Quote Start --- Sorry for all of this confusion, but I'm rather beginner then an expert. I can't sleep at night trying to find answers for these questions. --- Quote End --- Well, get some sleep.. Life is too short to get over worried about this. The "fastest way" to get something working would be to use an "off the shelf" solution attached to the FPGA. That way the HDMI protocol issues should be handled for you. http://www.terasic.com.tw/cgi-bin/page/archive.pl?language=english&categoryno=66&no=582 with a compatible dev board. For a board solution it adds BOM costs, but you'll save engineering costs. It also be used as an "intermediate" solution so you can have working video base-line while you work out the issues with your own solution. --- Quote Start --- Thanks Pete for your detailed answer. I will contact u if i hear anything from my manager. There is also this encryption part in HDMI. Is it smthg i have to consider? We won't need any kind of encryption for this application. //Update: We need help with a MJPEG or H264 encoder that can handle 1080p @ 60Hz. If you think you can help us with that we can discuss further price and target technology. Footprint should be minimum for Cyclone III, EP3C10. --- Quote End --- No Problem: Someone else responded with an IP solution for this. That's probably the cheapest quickest way to get your H264 encoder vs me building you one, but if you still need some help implementing, let me know. If you want to talk to me directly, our company number is 509-922-5629 x327 INFINETIX Corp. Pete
