FPGA Replay Board

[freqmax]

The ARM will re-init the board and file system if the chip is reprogrammed, so I can build and test very rapidly now without taking the SD card out.

Does this mean that if you saved anything on a virtual .ADF floppy on the flashcard those contents will be lost at re-init?

[freqmax]

Has there been any damage or failures when connecting or disconnecting devices when the FPGA Arcade is powered?

[freqmax]

Why is "AB3D II The Killing Grounds" such a good testing software?

[freqmax]

There's only only one memory channel physically asfair? and the other possible one is CPU<->fastmem on daughterboard. Provided you have a physical CPU inserted.

[freqmax]

I think the basic problem is that CPU + custom chips share the same memory interface. And the screen updates need a constant amount of bit per second.

[freqmax]

I have made some tests using bustest and my A4000 and both of my Replay boards (Rev.A with daughterboard and standard Rev.B). What do you think?
[CODE]
BusSpeedTest 0.19 (mlelstv)   Buffer:     262144 Bytes, Alignment: 32768
memtype   op    A4K PAL   A4K VGA   A4K RTG   RP PAL   RP VGA   060 PAL   060 VGA   060 RTG
fast    readw    33.7   33.6   33.7   20.9   19.4   52.9   52.3   52.8
chip    readw    1.7   0.7   2.3   5.8   4.7   7.1   7.1   7.1

My conclusion:
 * Video modes that use more bit/s will leave less capacity for other stuff.
 * Faster memory  interface = more capacity
 * Separate memory for CPU = faster read/writes

The RP+060 is perfect in all those aspects.

[freqmax]

I prefer touchpads, much less problems for the hand with them.

[freqmax]

I'm working on a new board which integrates an FPGA and 060 CPU together with other goodies. It won't be a direct replacement of any existing Amiga mainboard.

Will it have Ethernet (100Base-T) ..?

[freqmax]

Yes, there are plans to create another daughterboard with a bigger FPGA which could act as high-performance CPU. The question remains: who will make the CPU core?

Make some boards available and the code already used in the FPGA Arcade such that many people can tinker with it.

[freqmax]

I for one, do not trust the speed assessments given by the simulation software.

One can always measure number of instructions executed per clockcycle with VHDL simulators.

[freqmax]

Simulation is a lot of calculations really fast

[freqmax]

We'll have Natami cores just in time to use them on our BoXer boards.

BoXeR?

[freqmax]

Wire inductance, wire capacitance and heat issues are usually the factors that limit the speed (asfaik).

[freqmax]

The rumours of the TG68 death is overrated


Wonder what is the best modded-TG68, FPGA-Arcade68, or Natami050? or perhaps more importantly. Which ones that can be merged and make use of the benefits of its ancestors.

[freqmax]

So why not just have a faster 68020 CPU in FPGA rather than adding a real 68060 daughtercard?

The current FPGA Arcade, FPGA chip has a limited logic matrix as it has to handle graphics, sound, disc, memory etc.. too. There's also a limit on the gate to gate latency.

You could use a separate FPGA module as a I have suggested previously. That would give more logic matrix to work with. But leaves the latency issue which can be solved by using a manufacturer that specialize in faster variants.

You can put a 1 GHz crystal in your A1200..but buy a fire extinguisher and a miggy replacement first

[freqmax]

Did you measure the connectin diagram of the non-working vs the working ones?