Home Page Forums MAME MAME Monaco GP Emulation

Hello everyone,

I made a post on the MAME reddit page to let everyone know that I wanted to get Monaco GP on the working list for MAME. A user named Alternative_Glove_77 was kind enough to give me all the information I need to get started and wanted me to get on the bannister forums to help me in my journey.

My resume includes extensive experience with Electronics repair and design. I have a software engineering degree which includes the following programming languages; C++, C# Java, Visual basic, ASP, SQL and html with C# being my strongest language. I am teaching myself VHDL for some FPGA projects that I am working on for my side business named PinHead Electronics. I am currently a test Engineer for Orscheln LLC and they have a need for LabVIEW work, so I am in the process of learning LabVIEW as well. Unfortunately, my weakest language is C++ as I never used it professionally with any company I worked for and it's been 15 years since I used it in college, so I am a bit rusty to say the least. This means I will be hitting the books hard to get up to speed with C++.

I have always enjoyed MAME ever since its initial release and I have always wanted to contribute to the MAME community, but never took the plunge until now. I feel my experiences throughout the years have given me the required knowledge to finally give back to this great community. I think my biggest challenge will be the C++ part, so any help in this field will be greatly appreciated.

I initially looked at the DICE source code and I was able to understand a good amount of what I was reading. However, Alternative_Glove had me look at the Monaco GP driver and the Netlist cpp in MAME and I was not able to get a good grasp of what is being accomplished at this moment in time. I am hoping that a good design flowchart or document exists that I can read to help me to understand the MAME structure/design flow. I also looked at the pong files since this game is already functional in MAME, but I could not find where the connections for the ttl logic are defined for the game. I saw that DICE uses the SDL (Simple Direct Media Layer) for video translation and I am curious if MAME is using the same dll for the four emulated non cpu games. I also see that the device list for the TTL chips is much larger in DICE then it is in MAME. I haven't read the DICE license yet and I am wondering if it allows MAME to use some of those definitions for the TTL library outside of the DICE environment. I am assuming that the answer is no, because it probably would have been done otherwise.

I hear that Monaco GP has a mix of analog and digital circuitry, so I took a quick look at the schematics and saw that the A and B boards are digital, and the sound is analog. I haven't looked at the led board yet, but I assume it's mostly digital. That being said I am going to start with the A and B logic boards. Second, I will work on the Led output board. Then I will attempt sound. I am not sure how I want to attempt this yet, but I have thought of a few options. One would be to simply record each sound which would be the simplest way just to get it working but won't be very accurate. Another option would be to use an analog to digital convertor which would be a better option. My third idea would be to simulate the analog circuitry much like electronic simulators do with the SPICE engine. I think that could possibly be the best option, since it is open source and a well-developed engine. However, I was doing a little research and much to my surprise, actually found where another MAME user was talking about using SPICE for analog sound, but it was shot down without any explanation as to why. Licensing maybe? I am not sure. Please tell me if you know the answer.

I noticed that my board set is different than the board set schematics I downloaded. So far, I cannot find a set of schematics for my board set, so if anyone has them, please let me know. Otherwise, I will have to manually make a new set. For reference my board set is 97092-P and 97091-P. The MAME Monaco driver has my board set listed as Set B. Alternative_Glove said we only have one rom dump for this board set, so I might have to do a rom dump if it is a different version. I have a potential problem with dumping the roms because I removed the boards and noticed that only one chip has ever been changed, so I am hoping I can dump them while in circuit because I don't want to solder on a board that is near mint. I have never attempted dumping a rom before while it was in circuit, and I am curious if anyone has been successful dumping roms using this method? The problem I would foresee is that you would be powering all of the ttl logic and powering the entire data bus as well, which I think could be problematic.

So that's basically were I am at for the moment. I am excited to start on this project and I am open to absorbing as much knowledge and feedback as possible to help me through this venture. I will try to get some high-resolution pictures of the boards. I have an old Nikon D80 with a Macro lens, so I should be able to get some good pics. Also, can someone point me in the right direction to the file that contains the connection information for pong, so I can get a general idea of the methodology used to connect the ttl logic? I assumed it would be one of the netlist files I did not see it anywhere.

Hi, do you mean https://git.redump.net/mame/tree/src/mame/atari/nl_pong.cpp ?

Yes, that's the one I am looking for, thanks.

I need to clarify what I am saying about my sound ideas in my initial post. I mentioned three ideas, one to record, one for ADC and SPICE. My first idea-record just means to record a sound coming directly from the speaker into a mic and record into a .wav file. The second idea-ADC would be to connect the original sound circuitry to the recorder before it gets amplified, which will give a cleaner more accurate result. After thinking about my 3rd idea using SPICE, I realize I didn't think that one through. SPICE can simulate the circuitry but then what do you do with that information? You still have to digitize it at some point, so we don't really gain anything. I saw an article stating that the MAME team already has come up with solution for analog circuitry using a static solver routine, which works in a similar way to SPICE. That being said it appears to me that a lot of the groundwork has been done already, which will make my job easier. I hear that this method is very cpu intensive, so that could be a potential problem.

Thanks for working at this game. MAME already contains a variant "Monza GP" that although still broken (no collision detection etc.) at least makes a picture. AFAIK it was a modified bootleg variant that replaced some of the game logic with a CPU, so the MAME code may help to get the Monaco GP TTL hardware running. I had played Monza GP as a kid in the entrance hall of an indoor swimming pool. I hacked it by wiggeling/replugging the mains plug until it crashed to freeplay mode (only LED displays showed segment garbage instead of score).

Here is some info:
https://www.vernimark.com/arcades/videogioco/monza-gp/

I will check out the source code. Thanks for the information.

You should probably ignore what Windler has to say, and focus on learning from the existing netlist source files. If you're the person simzy pointed here, then it does sound like you're far overthinking things before you have even taken the time to learn MAME's codebase. Try to walk before running - like being aware that MAME already has an mixed analog/digital solver like SPICE.

What you should do is implement the entire circuitry as a netlist, just like other existing TTL games supported by MAME - Pong and Breakout, mainly - have been. Be aware that the actual developers replying to you in that Reddit thread are telling the truth: It will be extremely slow, and unlikely to run full speed. You will also most likely have to add the occasional TTL chip, transistor, or op-amp model. It's still worth doing, but it's also important to have realistic expectations.

Thanks for the response, since I can't find schematics for set B I am going to write fresh schematics for it. I will be taking pics of the boards and I can upload them as well. Once that is done I will strip all of the parts from the boards and start connecting the dots. Once that is complete, I will start on the netlist. In the meantime, I see stunt cycle has a lot of work done on it already, so I will be studying that netlist to see if I can figure out some of the issues with it as well.

http://forum.arcadecontrols.com/index.php/topic,134445.0/all.html

This thread about making a remake of Monaco GP contains plenty of resources. Apparently the thread starter geecab does have arcade schematics. They mention that there was a version in MisFit MAME/HBMAME, but I don't know how accurate it was and if it was technically a real emulation at all.

To my knowledge they are both remakes. I did find schematics for Set A but I have Set B and I cannot find anything for Set B.