MiniMig: One Random CRAZY Thought.

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little wrote:
emulator on a card, you can already do that in software, why do you need a PCI card also?

Software emulators will in most cases not be upto the latency requirements of the original. Also synchronisation may be lost. Parallel operations are possible with hardware in a whole another way.

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@alex:
Got hit by an Enterpoint product? :-D

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Just reading a bit on FPGA (Xilinx) and SDRAM & DDR. Which memory type to bet on?, SDRAM memories are available in abundance from old x86-pc ram modules. DDR maybe offers a more future proof path..?

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Any pipelined dram may actually waste a lot of (dram) clock cycles as the Amiga doesn't really expect such functionality.
So a SDRAM would then receive a read command, wait1, wait2, get data and continue (or something similar).
DDR1 in essence just seems to be about different pipeline depth and voltage.

DDR2 and DDR3 use voltage levels that may be incompatible with the FPGA. At least there's currently no onboard supply to drive them. So EDO, SDRAM, DDR1 seems to be the choice of DRAM in that order.

Sidetrack: Seems SDRAM is tested with 50 pF bus load and each input is max 3,8 pF. So it should be possible to drive an array of 12 SDRAMs with one bus to accomplish a large ramdisc.

@Belial6:
Considering that most pre DDR2 dram is dirt cheap these days. I think the rational choice is to go for the simplest dram to implement.

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@jkonstan:
What do I have to do when it comes to pcb layout to make sure SDRAM will work?

Also what DRAM access time does the 7.09379 MHz Minimig demand? (it had four cycles or so?)
The current sdram is 70 ns. But that's maybe faster than needed.

@little:
EDO is the "last" dram that don't use any real pipeline. But it might be harder to get a hold of in the future.

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I think what's sought after by the OP is essentially an Amiga graphics card that can be used on modern hardware. There is already a project that may be altered for that purpose:
http://en.wikipedia.org/wiki/Open_Graphics_Project

It even got 2x DVI :-)

@jkonstan:
I guess I was looking for thumb rules. Most Minimig boards will be 2-layer at most.

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koaftder wrote:

freqmax wrote:
I think what's sought after by the OP is essentially an Amiga graphics card that can be used on modern hardware. There is already a project that may be altered for that purpose:
http://en.wikipedia.org/wiki/Open_Graphics_Project

It even got 2x DVI :-)

@jkonstan:
I guess I was looking for thumb rules. Most Minimig boards will be 2-layer at most.

Oh man, what a waste of time. gfx cards are soooo cheap these days, whats the point? And AMD is making all the radeon specs OS anyway. Why, oh why, reinvent the 10 dollar wheel?

That project was born when graphics manufactors refused to give documentation that allowed drivers to be written for free operating systems like FreeBSD, NetBSD, Linux etc..
This is especially true when it comes to 3D usage.

ATI and NVidia binary blob drivers that are supposed to solve this problem for end users are poorly written, and doesn't work alright with software upgrades or non-x86 architectures.

I have heard that Intel and ATI are more documentation friendly at the momement. But NVidia is a particular rotten egg in this department. So NVidia hardware are ditched by many that want unix on their machines because of their refusal to provide documentation to driver writers.

The OGP card also gives the possibility to experiment with new computer graphics hardware algorithms.