Lattice ECP5 challenges to solve,before get my hands dirty! - Page 1
Forum section: electronics / projects

author: ali_asadzadeh
author_rank: Super Contributor
timestamp: May 26, 2018, 02:12:29 pm
content: Hi,I have taken a look at these babies,http://www.latticesemi.com/en/Products/FPGAandCPLD/ECP5The good point about them that attracted my eyes are lower prices, and 0.5mm pitch BGA packages, I have these questions before I get my hands dirty on these babies.First of all is there a free license for using the software for them, especially the ones with SERDES ? I have read briefly their documents and saw that they managed to route all the balls on a 4 layer PCB for the 285 csfBGA package! using only 0.1mm Vias!?So are those Vias laser drilled Via? what sort of prices should I expect for the PCB tooling and manufacturing costs?Also I have seen they have used a FT2232H device for JTAG, is it open source or should I buy a separate programmer?can I connect a DDR3 16bit wide memory on a 4 layer PCB to these chips?what is the learning curve of using lattice diamond? is it huge? since I have experience in ISE and vivado.what about the IP's availability? are they free? what about the SERDES IP's, for example PCI express, Ethernet or HDMI?And finally does this family worth doing projects?

author: daveshah
author_rank: Unknown
timestamp: May 26, 2018, 02:50:44 pm
content: In my opinion the ECP5 are great FPGAs, that's why I'm working on developingopen source toolsfor them! But don't expect anything on that front until at least mid next year.As it stands you will need a Diamond license for the SERDES parts. Some evaluation boards do include a license voucher, but I think it's limited to the exact part number included on the board (I don't have one myself, so I don't know if it limits you to the same package only also). I think Lattice have had promotions on the Diamond license in the past too.You can use any FT2232H device to program them, copy the wiring from an evaluation board and it should work fine with Diamond programmer.Diamond shouldn't be too hard to use if you've used ISE and Vivado before, but don't expect it to be as polished as Vivado. It does tend to work reasonably well though.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: May 26, 2018, 03:25:15 pm
content: Diamond is extremely similar to ISE in many respects

author: daveshah
author_rank: Unknown
timestamp: May 26, 2018, 03:45:44 pm
content: Quote from: mikeselectricstuff on May 26, 2018, 03:25:15 pmMany core parts, including place and route, are effectively identical - Diamond is based off NeoCAD, because AT&T bought a NeoCAD license then their FPGA division ultimately ended up part of Lattice; while Xilinx bought out NeoCAD and used their software to build ISE.

author: ali_asadzadeh
author_rank: Super Contributor
timestamp: May 27, 2018, 12:29:31 pm
content: Thanks for your answers,daveshah does the FT2232H EEPROM contents matter? also have you done a PCB project on them?Also what about the availability of the parts, specially the 285 csfBGA versions?What about the PCB related questions, are the 0.1mm vias laser drilled? what sort of prices should I expect?can I connect a DDR3 16bit wide memory on a 4 layer PCB to these chips?

author: daveshah
author_rank: Unknown
timestamp: May 27, 2018, 02:46:45 pm
content: I've worked on other Lattice boards, and Diamond doesn't care much about the EEPROM, it may well need to be in MPSSE mode and I think it needs the standard VID/PID, but not more than that (unlike Digilent/Xilinx).Haven't ever built my own ECP5 board yet, but looked into it for the future. The availability of the ECP5 has looked reasonable OK when I've looked, at least the no-SERDES and 5G SERDES versions (for some reason the 3G ones can be a bit harder to find).My experience from other FPGA boards is that for DDR3, although 4 layers is possibly technically doable, 6 layers is a lot nicer. I think the csfBGA package has quite a few ground balls and some voids which make it fairly easy to use. When I've done 0.1mm via stuff they haven't been laser drilled, I think.

author: ali_asadzadeh
author_rank: Super Contributor
timestamp: May 28, 2018, 05:07:30 am
content: Thanks daveshah, that was very helpful, would you please tell me where you manufacture your boards with 0.1mm vias?

author: daveshah
author_rank: Unknown
timestamp: May 28, 2018, 06:32:55 am
content: Both of those projects used ALLPCB, because I was also using their assembly service. The PCB quality itself has been good but the assembly quality was patchy the second time I used it (some parts missing and some 0201 parts very badly soldered).

author: ali_asadzadeh
author_rank: Super Contributor
timestamp: May 28, 2018, 09:22:15 am
content: Thanks daveshahI have registered in lattice website tow days ago, when I try to download the Lattice diamond it says thisQuoteWhat's wrong with their website? did you have any issue regarding registering in their website?