Hello,
One thing that just came up in another forum is the matter of routing PCB tracks for DDR3 RAM, and this is probably a topic that was encountered by both the Pyra...
https://pyra-handheld.com/boards/threads/analyzing-4gb-ram.81687/
https://pyra-handheld.com/boards/threads/is-there-really-a-light-at-the-end-...
...and the EOMA68 initiatives. Is there any pertinent documentation describing this exercise in the EOMA68 board design process? Searching for DDR3 on the Rhombus Tech site [*] indicates that some boards were done with guidance (at some level) from the vendors:
http://rhombus-tech.net/ingenic/jz4775/news/11jul2014_routing_completed/
http://rhombus-tech.net/allwinner/a31/news/
Previous discussions of KiCad and Olimex boards, which presumably involved DDR3 routing, can be found via this message:
http://lists.phcomp.co.uk/pipermail/arm-netbook/2019-May/016062.html
I ask about this in the context of someone who just made design files available for a board using the Ingenic JZ4780 that they had been working on. Those files are here:
https://gitlab.com/igagis/cranberrypi
Paul
[*] http://rhombus-tech.net/cgi-bin/rhombus/ikiwiki.cgi?P=DDR3
--- crowd-funded eco-conscious hardware: https://www.crowdsupply.com/eoma68
On Sat, Jul 25, 2020 at 4:58 PM Paul Boddie paul@boddie.org.uk wrote:
Hello,
One thing that just came up in another forum is the matter of routing PCB tracks for DDR3 RAM,
yes. it's a pig. specialist people with a huge amount of expertise can do it - or, if you have the right proprietary software, much of it can be handled automatically.
...and the EOMA68 initiatives. Is there any pertinent documentation describing this exercise in the EOMA68 board design process?
put simply: i take an existing Reference Design, do *not* touch the DDR layout - at all.
that's it.
l.
arm-netbook@lists.phcomp.co.uk
-
Luke Kenneth Casson Leighton -
Paul Boddie