Topic: FPGA development board "Lancelot" - accept bitsteam developer's orders. - page 4. (Read 101892 times)

Hello,
I have done some examinations and I think I found the resistors...
I write here for confirm if I am right or not. So I do not guarantee it at all!!!
Could someone confirm it?

(You can see the boxed text in the status bar of the schematics where it is written the name of the component selected with its value)

R47:

http://anonymouse.org/cgi-bin/anon-www.cgi/http://anonymouse.org/cgi-bin/anon-www.cgi/http://img20.imageshack.us/img20/1702/r47h.jpg

R56:

http://anonymouse.org/cgi-bin/anon-www.cgi/http://anonymouse.org/cgi-bin/anon-www.cgi/http://img839.imageshack.us/img839/4534/r56rz.jpg

After 2 hours of fight with ISE WebPack finally I was able to load new bitstream. Of course, ISE throw on me some idiotic messages insted of simple one that would say "Hey idiot, iMpact do not support slx150 becuse it's a part of WebPack". Reinstall and new lic key done the job right
Mine board achieves 420MH/s (batch 1). Cgminer doubles that and shows 840 . I've run it with option --icarus-timing long. Reported values are also wrong 1.2ns and should be ~2.4ns. After tommorow I will solder ekstra resistors and see if that will improve performance.

Oooh! yes that is...
Thanks

yes, an image about v1 and v2 differencies and location of resistors will be great!

nghzang (or someone else),
i am not good with hardware at all. is it possible just to take a shot of lancelot an mark where two resistors are. otherwise i have a friend to do soldering for me but pcb schematics are beyond our knowledge

 

sorry guys, i test the bitsteam with the 2nd batch of Lancelot, which is default using 9.09K（9.1K can use） for R56 and R47. (1.24V Vcore)it's about 20~30% improvement compare to V3.

today i find a very few 1st batch Lancelot, with 10K for R56 and R47. (1.16V Vcore) it seems will much slower than the 2nd batch. but on average there is still about 10%~15% improvement.

so if possible, i suggest you to change R56 and R 47 for a additional benefit. notice that the 2 resistors is very important, the soldering quality is important. and do not let Vcore above ~1.3V when idling.

how to know which board is 2nd batch: all 2nd batch board have a soldered black 40PIN header, that 1st batch haven't.

I faced the same issue. It was because you trying to flash a corrupt bitstream file.

I suggest you download the whole Lancelot project file as a zip file and then unzip it locally in this way you could got a correct bitstream file.

Hello,
I have installed 13.2 and when I try to do the flash I receive this message:
ERROR:iMPACT - The assigned file exceeds the capacity of the largest flash device supported for indirect flash programming using iMPACT.

Any answer for this??

Why can't we have a different bitstream on each FPGA ? apart from the timing (--icarus-timing default=xx) I don't see why it wouldn't work ?

42 : I was of course referring to the hitchhiker's guide to the galaxy

Super!
------------------------
add some core voltage will help, default Lancelot core voltage is 1.16V, you can change it to 1.26V by change R56 and R47 to 9.1K. certainly, there are risks and more heat.
------------------------
Can you give us some info what additional boost are you getting when changing the resistors. Heat and power are no issue since winter is comming:)
I just want to know the numbers to make my decision. For instance difference in performance "%" between your best board with 42 bitstream stock resistors compared to same board with  R56 and R47 to 9.1K?

10X

yep，same as icarus V3.
by my test, 95% boards will get a at least 20% promotion, over 50% get more than 30%.
add some core voltage will help, default Lancelot core voltage is 1.16V, you can change it to 1.26V by change R56 and R47 to 9.1K. certainly, there are risks and more heat.


maybe some new slower bitsteam for icarus will announce soon.


don't do that.

about why is V42: it's the 42 version last month... 

will continue improve it, but .. i hope will some more smoothly. 

That sounds great!

Ngzhang you are the one to be trusted!

Thank you very much!!!

I will test it in the evening.
Just a side question. Where we can get default Lancelot Bitstream just in case? Is it same bitstream used with icarus V3?
10X

> 1, not recommend for icarus board. but you try if you can take the risks.

I tested it with my Icarus. Could got 350 MHash or so. (Tested under RG7Miner). Finally I rolled it back to version V3.

Try to flash only one FPGA ? Maybe only one of the two is making all the errors

A:3670 R:57 HW:79 U:4.9
not working for me
going back to default bitstream

@luffy : you're welcome


I updated to the latest version of cgminer,


Just about no hardware error, gain is ~ +20% (420 MH/s instead of 380)
Maybe it doesn't go higher because I don't have a fan blowing on the side, I'll try that tomorrow and will report if it makes a difference.

Do you think I can program the PROMs of the board now ?

[Edit] I just Flashed both chips. This works better than V3 at any rate

paste a guide here.

warning:
1, not recommend for icarus board. but you try if you can take the risks.
2, if the board running abnormal, please switch back to the 380M bitsteam.
3, if the board invalid rate is higher than 10%, please switch back to the 380M bitsteam.
4, not guarantee every Lancelot board can normally operation with this bitsteam.
5, recommend you to use 42.bit for Interim test, it will lost if you turn off the board.

features:
1, fully auto speed regulation. about 460~520MH/s on Lancelot board.

how to update:
1, install XILINX Lab tooles (or ISE). i use V13.4. V14.2 may have some strange issues.
2, find and open "iMPACT" tool. press "cancel" if any dialog box popup.
3, connect the Platform Cable, power the board. the indicator light on the cable turn green.
4, click " Boundary Scan".  click "Initialize Chain". press "cancel" if any dialog box popup.
5, click "SPI/BPI ?" icon at the top of xc6slx150 device. and assign the MCS file. delect "SPI PROM", "W25Q64BV/CV", "1".
6, repeat step 5 for the other FPGA.
7, right click FLASH icon and select program.
8, wait for at least 8 min, than it will success.
9, turn off Icarus, and tun on. you will find the FLASH is already updated.
10, do  7~9 for the other FPGA.
11, finish.

Tips:
1, will significantly increase heat and power. about 23W pre board. so you need a power adaper can provide 12V@2A continuously.
2, cooling is very important. please DO NOT remove the original heat-sink and fan, they are enough for the top. use another fan blow from the side. the PCB it self is a heat-sink too.
3, not recommend for voltage adjustment. but if you want to do so, i don't block.
4, a typical invalid rate is 5%.
5, Job interval time can use about 6~7S for a better performance.
6, the speed measure is not accurate this time. please check the "shares pre hour" for a speed measures.
7, the JTAG pin is at bottom left of the board. from left to right: VCC/GND/TCK/TDO/TDI/TMS

thanks flynn,
you are the man!

Lancelot
For the connection =>

https://bitcointalksearch.org/topic/m.1167844

(board seen with JTAG at the bottom left)

are you talking about icarus or lancelot?
it seems i have misplaced the paper included in the development kit and i don;t know how to connect JTAG to Lancelot
moreover the JTAG cable has 7 pins but the board only 6?!