FPGA Replay Board

[freqmax]

Do you use DCM to adjust the DRAM clock signal?

[mikej]

Do you use DCM to adjust the DRAM clock signal?

Yes, exactly. The output timing is fixed.

There is no need to use the DQS strobes for capture at these speeds.

There is a careful handover of return valid internally and then a phase change FIFO to capture the data. These params are adjustable during DRAM training, however I have found I can fix them to a common value across all boards, the margins are so large.

/Mike

[Darrin]

@ MikeJ:

Any chance if that new core in the next week?  If not then I'll be away at work for another 4 weeks.  I need my FPGA Arcade fix.  

[mikej]

@ MikeJ:

Any chance if that new core in the next week?  If not then I'll be away at work for another 4 weeks.  I need my FPGA Arcade fix.  

mmm Not sure it will be 100% stable. It's close, mail me mid week.

[Johan Samuelsson]

Yeah! Nice update MikeJ! Thanks!

[elpiloto]

Hi all,
Im really intrested on buying one of this boards, is there any contact information? I sent an email some days ago, but no response yet....

[mikej]

Sorry, bit behind with emails.
Update ...
Production is complete now. It is raining in Shenzhen and this is delaying the cardboard box delivery. The boards should be shipped out end of the week.

This means I get a little longer to keep playing with the core. It's all good though as I am working on fixing the cache and prefetch logic. The DRAM controller is designed for the daughterboard and has a 32 bit data path for efficiency. This means a bit of logic an endian-ness fiddling is required to attach it to the 68K softcore.

To fully test this, the VHDL testbench now loads an srec file directly into the DRAM at start up and I simulate the processor running with various tests, stalls, refresh etc.

/MikeJ

[Hattig]

Sounds good. Hope that we start seeing some videos on YouTube soon of the new cores running on the finished hardware!

[freqmax]

Completely OT: How does one find food in China that one dears to eat without getting lead or other slowly poisons?
(I read the party people has their own organisation for this purpose out of reach for ordinary people)

[Darrin]

Completely OT: How does one find food in China that one dears to eat without getting lead or other slowly poisons?
(I read the party people has their own organisation for this purpose out of reach for ordinary people)

When I worked over there we had a KFC, a McDonalds, an Irish pub that served fish n chips and a French steakhouse all within walking distance of the office.  :-)

[mikej]

It's improved a lot, some really good food in SZ.
It's the street dumplings you need to watch, they seem like a good idea after a few beers - and very tasty. They can fight back though

[psxphill]

The DRAM controller is designed for the daughterboard and has a 32 bit data path for efficiency. This means a bit of logic an endian-ness fiddling is required to attach it to the 68K softcore.

As long as the ram is only accessed by one cpu then the ram is endian agnostic.

[utri007]

Could it be possible to get some kind of short product information?

I would be interestd performance, with and without 060 module.
What are possibilites with graphics.
IO possibilities
RAM

etc.

[freqmax]

When I worked over there we had a KFC, a McDonalds, an Irish pub that served fish n chips and a French steakhouse all within walking distance of the office.  :-)

Lead, pesticides, motor oil and other spices included free of charge?

[mikej]

As long as the ram is only accessed by one cpu then the ram is endian agnostic.

Sort of - you have the ARM direct memory access, the video controller and other bits and bobs. The 68060 has pretty strong ideas about which byte enable correspond to which bits, which my memory controller happens to disagree with. Then, the problem of 16 bit vs 32 bit access to the memories.

As a hardware designer, little endian is a whole load easier, byte 0 stays where it is no matter what the access size.

/MikeJ

[Darrin]

Lead, pesticides, motor oil and other spices included free of charge?

They come standard with KFC and McDonalds.  They wouldn't taste the same without them.