(10 replies, posted in Arcade)

I have a REAL cockpit Star Wars Arcade( I modded it to allow a switch out of roms to play Empire Strikes Back !) big_smile I would like to definitely see Star Wars and Empire Strikes Back run on the FPGA Replay board.... it would then justify me selling my arcade and being able to afford a Replay board. OF course I would like to see the Replay be able to handle the original controllers... all of which are digital so no A/D would be required. IT uses X,Y encoders for the steering yoke and should be a cinch for the Replay....using Grey's code I would imagine.

Hey gamefixer...the old customs were definitely not the most stable chips...lotsa heat and all. Would like to see these done CLPD or small FPGA module with some other stuff. I do realize the issue with the analog parts but a few small chips could deal with that I bet. Maybe a pic or some other processor like that to emulate them could be useful.

Macro wrote:

The astrocade chips are a pain as they have an analogue element as well as digital. two customs also produce sound. The video chip kicks out a rather weird variation on component video, one chip handles analogue inputs (although I don't think any of the arcade games use them) plus you have the SC01 speech chip.

each custom chip replacement would basically need it's own board with discrete components to implement the analogue feature, which would put the cost up to the point where it's probably easier (and cheaper) to replace the entire board with a replay (or custom board) and it is something I'd also started looking at.

I have some working Gorf sets here, so along with the astrocade code hope to create something suitable (multigame anyone ....?)

as a sideline, I did quite a lot of the work on the Mame driver for Gorf, Wizard of Wor, Space Zap, Robby Roto etc.

Hi Macro,

I think a small 8 channel A/D chip would go a long way to help. I wrote the 1st code for MAME...to be more accurate,
I was writing a stand alone that I gave to someone to add into MAME. It would be nice if they gave me a little credit
for that....they did originally but over time forgot about me.  sad Oh well. smile

I know a lot of you folks really advanced the original code I supplied for the astrocade MAME emulator originally. I was
aimed at the home system when I gave the code to whomever it was...had to be a dozen or more years ago. Frank I think his name was. Someone added the pattern board emu-code and I have not been part of that for well over a decade now. I would really like to see someone properly emulate the sparkle circuit that does things like the shields in Gorf. I am still not 100% on how they do the backdrop star field, but I remember Bob Ogden telling me that is was a separate circuit.

Please keep me posted and I will help you where I can. Neither VHDL nor Verilog is something I have much experience with. I bought a Spartan 3E dev board years back and never really got my head around it. Too many years doing sequential code did not help with the fact that VHDL and Verilog are parallel. I am also electronically savvy to a point so I thought I would be a natural at it. Unfortunately, there are tutorials that approach it from an overly technical point of view and do not really consider us novices. I do however understand the astrocade hardware mostly from a software POV pretty well.

I'd love to see what you have in mind and how your progress is going. I know the Astrocade code Mike J did eliminates some important things like the four RAS lines needed to properly address the system RAM to use it in an authentic circuit so that would also have to be dealt with.

I think a MB replacement for the home system would be smashing idea. One that would also consider the other 3 banks or RAM so that hi-rez games could be done....perhaps add the pattern board circuit with the sparkle and backdrop star circuits. A truly and fully arcade compatible that can use all the old game carts as well.



(317 replies, posted in News)

WOW! That has to be the neatest and most organized electronis work bench I've ever seen...how ever do you do that? wink


(6 replies, posted in Member introductions)

Ok so that's is how you PM here... smile You should have gotten my email I sent it using Thunderbird as I am about to dump WLM.....EEEEEVil Microsoft sad


(6 replies, posted in Member introductions)

Ok Jim, but I tried that and my server will not connect with your email. It would be useful if we had some means of PM here.
I'd rather not give my email publically.

Hello Wolfgang( one of my all time favorite names ever!)

Mike linked me to this thread. I would like to know if we can take the Address, Data and I/O chips from the Astrocade
hardware( which is BTW both the same in the arcade and the HVGS home system) and pop these on similar devices.

I would really think that the Spartan family is over kill as these chips are not that hi density.

Perhaps I can work along you folks and fix a few things I noticed in the Astrocade code ( if there is a need to fix them at all)
and possibly fit these on much smaller chips and possibly bringing down the price of these as well?

There are a lot of non-functional Astrocade arcade boards as well as home systems that are collecting dust only
because these chips are no longer available.

Let me know what I need to do and what you need to help get this going if you are interested.

I have an Astrocade system update I am currently working on....IE a 50mhz Astrocade System
which will fit right inside an original Astrocade Console. If all goes according to plan, this new
system will run all original software and add many new powerful features. This however may not
require FPGA but I thought I mention it. smile

YAY! I am glad that it will be brought to the Replay board but what I am interested in is making separate Data, Address and I/O chips sets that would plug directly in the actual mother boards. I would imagine myself and other Astrocade home system and arcade system owners would be more than happy to be able to resurrect some dead boards( due to failed custom chips) Is it feasible to to use something smaller like a CPLD and program it to act like the original pin for pin? These customs are 40 pins btw. I do realize that these chips are usually 3 volts and probably would require some voltage regulation from the 5 volts on the Astrocade boards but I am sure they already exist. Keep in mind, there are plenty of us 'purists' out here ( whatever the heck that actually means smile ) who would like to keep our old hardware up and running.

I was actually looking at how you did some of the Address chip code and that you kludge( or what little I know about HDL code) this by moving the four RAS line down to one. That would probably need to be expanded out to use the actual 4 lines if replacement chips were to be made plugin ready for the existing boards.

If you were not already aware of how the address chip accesses memory for its 3 gfx modes, I was told by Bob Ogdon who was on the Nutting design team, that the way the Astrocade works in lo res mode, 160x102, is it requires only one bank of 4k by 8 bits using RAS0 as it's row address scan, but in the medium( yes this is a mode if you did not already know this which I do not believe any game ever used) res mode(160x204), it requires 2 banks and they have to be set up as 2 banks of 4k x 8 bits, which looks like 16 bits or 2 totally separate 8 bit paths to the address chip, RAS0 for bank 0 and RAS1 for bank 1. Then in the final mode, the hires 320 x 204 mode, you need all four RAS lines which are 4k banks of 8 bits each and according to Bob, these look like 32 bits or 4 totally separate paths of 8 bits each to the address and data chip.

I only tell you this as the 'kludge' you used in your code( not that I fully understand what you did there btw) tells me you may not have been fully aware of how this operates. I was blown away when I ran that on my Xilinx Spartan 3E, BTW...AWSOME!.

Could you give me a link to these 42 pin boards? I'd like to take a look at those. How expensive could they be?

Thanks for any help you can supply. It is well appreciated as I know you are very busy.


(6 replies, posted in Member introductions)

MikeJ wrote:

Hello and welcome!
Still a large backlog, but more going out this weekend...

It is good to know they are still available. It's even better to know that you have not given up on us hopelessly devoted old school gamers!! What is the cost of one of these boards anyway(US dollars)?

I have another question also...do we have the ability for PM's here? I have a few questions I'd like to ask you without cluttering up the forums.


Hey Mike,

I know you did a complete Astrocade unit a few years back. I and many Bally fans would love to see the custom chips from that system put into CPLD sized( as I imagine they should fit in those) replacement modules. There are a lot of dead Astrocade and Arcade machines out there that could easily be brought back to life it we could get these going. Is this something I could help you with? I could certainly take a look at the code and attempt to move the separate circuits to separate smaller CPLD's. Many Astrocade fans would be very grateful!


(1,708 replies, posted in Amiga)

Mike is an FPGA coding juggernaut! I just joined today and am looking at all the great work you are doing. I need to get me some funds to buy a Replay board!

I am pretty sure Mike already did the Astrocade and even so adding hi-res mode to it( at least the console), but I would like to expand upon that after I learn a little more about the FPGA basics and add the arcade extra's like the additional I/O chip and the sparkle circuits....unless Mike already did all this that is. smile


(6 replies, posted in Member introductions)

Hi folks!

Good to see the FPGA Arcade alive and well!

I was wondering what the current status of the replay board is and hope they are still obtainable!
Hope to learn a few things while I am here and hopefully one day contribute as well!