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POKEY RMT by Eckhard


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unbelievable but true but I want to get back to 7800 coding after 12 months of Lynx coding and decades of 800.


My dev setup looks like



- MAME with -debug option



so some question...


- How important is signing my binary for development purposes? (ok... later maybe on flashcard needed and real machine).

- RMT music player for 7800 and POKEY. I did not get the source assembled (always says my ROM is corrupt) but does anybody have an actual DASMed version of Eckhard's player conversion?

- what is the maximum flashcard configuration I can use to develope? I mean 4k RAM is a joke alone ;=) and 32k ROM, too... so Dark Chambers e.g. uses 128k ROM... Fractalus proto some additional RAM.


Thanks for letting me know... :)


ps. took me 5 hours to get my sources running again I have written 2003 (and you still find it here at AA :D)





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It's a good idea to sign your binaries if you want the home audience to play along. Most will be able to get by without the signature - a lot of bios images and flash carts skip it - but theres usually someone who will complain the rom doesn't work, if you don't sign it.


You might want to check out the 7800 Assembly Dev Kit. It has programs that make adding headers and signatures painless. Windows, OS X, and Linux are supported.


I think most flash carts support at least 128k, so that's a common large format. Easy to expand a 128k rom to 256k (not CC2 supported. Not sure about Matteos) or 512k. (CC2 supported). Physical carts can actually go bigger, thanks to CPUWIZ. MAME handles all of these.

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Thanks Trebor! You are the Indiana Jones of 7800 archeology. :D I also took this opportunity to mirror Eckhard's Bankswitch Guide at 7800.8bitdev.org, thanks to your archive.org link.


Heaven/TQA, I was able to build Eckhard's source with dasm and produced a binary identical to his, with the exception of the signature. The only change I needed to make on my Linux system was to change "include MARIA.H" in music.das to "include maria.h", matching the case of the file name... this shouldn't be required on a Windows system. Not sure what you're using, but perhaps that's the problem?


The line I used to compile it was: dasm music.das -f3 -I. -omusic.bin -lmusic.list


This will produce a "music.list" file which also may point to why the assembly is aborting.


If you're looking for a OS X/Linux makefile for this, let me know.

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Thanks!!! Works.... glad.... player seems to be based on an old RMT version but i will update it to latest 1.27/1.28.


Next question:


512kb, pokey, and 8k or 16k ram... possible as bank switching scheme with flash carts?


Can't answer the flash cart question, but I know my VersaBoard can do that.


31 x 16K banks

1 x 16K fixed bank (reset vector)

1 x 16K RAM



With a 512K NVRAM chip (and a special programmer for the cart), it can do 512K NVRAM + 16K RAM + POKEY. :grin:


Hmm, Ich glaube Ich muss mal wieder ein bischen basteln. :ponder:

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Thanks!!! Works.... glad.... player seems to be based on an old RMT version but i will update it to latest 1.27/1.28.


Next question:


512kb, pokey, and 8k or 16k ram... possible as bank switching scheme with flash carts?

Are you asking for your own flashcart needs, or just trying to work in a common format that others can try out?


CuttleCart2 can handle 512k, the Mateos Muticart can handle 128k/144k. Both have POKEY support and 16K RAM support, but not in the same ROM, because these carts hard-code both POKEY and RAM at the same $4000 address.


The Harmony Concerto is supposed to be able to use POKEY@450 (like an Xboard or XM) and RAM@4000, but it's still in development and stalled at the moment. The MCP DevCart can also deal with POKEY@450 and write into it's NVRAM@4000, but uses bankswitch hotspots in a location different to the standard SuperGame format.

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Got ya. That makes it easier.


CC2 and Mateos can't do extra RAM+POKEY at the same time, so you can rule them out.


I'm not sure if CPUWIZ has inventory for the MCP cart anymore. If he does, that will get you 128k+RAM+pokey. (with pokey@450) That's a bit on the lightweight side of what you want.


Concerto is supposed to support up to 1MB ROM, pokey@450, and 16kRAM. But it's not done yet, and in it's current incarnation it's incompatible with some % of consoles. Batari has the project on hold, but you might be able to buy one of these from one of the guys that ran into compatibility issues. No guarantee you won't run into compatibility issues or bugs too, so I'd say stay away from this for now.


Given all of the above, if I were in your shoes and wanted a maxed out real-hardware config, I'd see if I could buy a few configured Versaboards from CPUWIZ and thrown an eprom socket on them. It's not as handy as a flash cart, but it would be just fine for real hardware tests. (or similarly, use the NVRAM writer he suggests)


It's probably worth mentioning that the MAME 7800 driver was updated to behave very close to real hardware a few years back. It doesn't quite get rid of the need for real hardware testing, but it really does mean that you only need to do real-hardware tests on your game/demo at major milestones. When I worked on adding double-buffering to 7800basic, I tested exactly once on real hardware, right at the end; that's how confident I've become in the emulated results.


There may be issues discovered between emulation and real hardware testing where I'll need to tweak - e.g. if my code relies memory cleared by the emulator, or relies on mid-line color changes. But I'm now confident the MAME 7800 emulation won't let me paint myself into a design that will only work in emulation. Those days went away for it when DMA timing, DMA timing limits, and graphics modes were correctly emulated.

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But sad there is no cart then which can do ram+pokey... I would sacrifice ram just to heave pokey because we have several musicians In desire group... and Tia is so limited and would not fit the visuals.... Lynx was hard in that term.


But 4K ram how the hell can you deal with double buffer with dynamic vram??? Don't see yet how.... (bitmaps even rouge that out) that's why RoF had 2k extra ram on cart.

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Yes.... but available?


CPUWIZ mentioning his Versaboard, and RevEng suggesting to "...buy a few configured Versaboards from CPUWIZ..." means availability. ;)


The imminent release of Bentley Bear's Crystal Quest to the AtariAge store utilizes the Versaboard, as does the relatively newly created Donkey Kong PK, including the special edition that was just auctioned.


Granted, both games utilize far less than 512K; however, they both utilize POKEY, and as mentioned, the Versaboard can be configured to handle 512K NVRAM along with 16K RAM. :)

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re: pokey player


does anybody have tried to use another RMT? in Mame even the Delta.rmt example does not played back correctly. Right now I did not managed to get a RMT example assembled.


the supplied music.a78 even does not sound correct.


I tried 1.28 of tracker and even when I go back to 1.20 (as Eckard's source states) it's not played back correctly.


any ideas?

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