*** New Multiboard RaspberryJAMMA ***

[dee2eR]

This is just my hobby so there's no shop or site to link you to, sorry. Good idea not to order before Christmas, it probably wouldn't get there before Christmas anyway.

Basically I build each to order so it gets cheaper the less bits needed.
complete unit ready to plug and play including pi2 and Sandisk class 10 8 gig Sd card is AU$205 + delivery
same without video on JAMMA for high res use AU$200 + delivery

got your own pi? take off AU$50 for one without pi.
want the probably unnececary heat sink for the audio amp? $5 extra, but it isn't really needed anyway.

Delivery to the UK was AU$18.20 for one board, the delivery price doubles for 2 but 3 may fit in the same bracket as 2, I'm not sure, it'l be close. Sorry to quote AU pricing but exchange rates constantly change.

 

[limpy]

great,more techy gizmo's i simply must have.
must sell something though.whats the going rate for children?? do you need a 14 year old step son? LOL

 

[swisstoni]

Ive added a quick video from my phone to the bottom of the original post showing a few games running, no screen tearing, good emulation (im using Mame4all in this video), the board was running on an Astro City, I attached a keyboard (not required) to the board just to the show mame menu can be accessed, also a few close up shots to show the scanlines, much better than the Pandoras Box and Game Elf boards ive owned before The picture is perfect it may just come across a bit fuzzy on the video, will try and do a better video showing some other games and upload asap.swisstoni2015-12-13 12:24:01

 

[rcantor77]

So what is the problem with this running on a Multi Sync monitor... if the Pi is forced to output 15KHz then surely the monitor will change accordingly.

 

[dee2eR]

So what is the problem with this running on a Multi Sync monitor... if the Pi is forced to output 15KHz then surely the monitor will change accordingly.

I'm actually not sure what went wrong when I tried it. Pretty sure the pi was set to 480p at the time though. Was at a mates place and I didn't want to hurt his gear. I don't own a multisync to work it out but I suspect there's a good output resolution to be found in the pi that would make it work.

 

[rcantor77]

Only ask as I have an auto switching Nanao MS-2931 in my Blast City... sure it will be fine but might just need some config tweaks.

 

[Beaps]

I am pretty clued up on Pi2 and the versions of MAME it runs are pretty much dated. I am more interested on the bottom board and how it converts HDMI to VGA then how it converts that to 15khz.

 

[dee2eR]

I am pretty clued up on Pi2 and the versions of MAME it runs are pretty much dated. I am more interested on the bottom board and how it converts HDMI to VGA then how it converts that to 15khz.

All you really need is a HDMI to VGA converter which doesn't mind non-interlaced 15k. Which to be honest is the bane of this project. Most of these converters suck and everytime I've ordered more than 2 at once I get high res only or converters with no audio out etc. I designed the converter into the board at one point however the chips could only be bought in really high numbers so I shelved that design. I kinda regret that but the numbers are still crazy.

The HDMI signal is 15k low res before the converter. The HDMI to VGA converter is really just a digital to analog converter as well as a good place to seperate video and audio signals.

Theres no hope of this working if your device doesn't output 15k non-interlaced lowres already.

 

[ColinD]

I was wondering about getting the pi or an odroid to spit out low res 15khz, but when looking at the spec of the hdmi convertors, I could only find ones listed with 480p etc and not 240p ...

This is for the Cannonball project which uses outrun pinouts/motion control etc and is not jamma. The new pi2 might be man enough to run the graphics and sound without any frame dropouts, I'll have to consult Chris , if not we just have to wait another year or so for more power !!

dee2eR, can you PM me your contact details please ? - I would love to know a little more how you achieved this please. The CannonBall and my Cannonboard work in progress can be found here.... CLICK THIS LINK

I was at one point looking to have a serial eprom to produce a fake monitor id with the low resolution for use with a small form pc motherboard and other devices but I've not had time to investigate more.

Thanks, ColColinD2015-12-14 20:13:28

 

[devtty0]

I tried to PM dee2eR yesterday, to order one of these however I just realised that he probably doesnt have enough posts to get access to PM's .. if you come back here, dee2eR, ccan I order one please

 

[guddler]

[EDIT] Fixed. Dee should be able to send and receive PMs now so might be worth resending any that have already been sent. I don't have time right now to look into if any are waiting or not.guddler2015-12-15 11:44:48

 

[Ravi_s]

Nice little solution shame its based on the pi2. I assume you would be limited to really old version of mame/romset. On the plus side the solution is plug / play and just works.

Alternative solution maybe to strip the main board out of hp microserver.
These boards have a built in Ati graphics card that is now supported by crt emu / groovy mame on Windows 7 possibly xp / linux too.. simply build or buy a vga to scart cable or if using a arcade monitor use jpac adapter. Once your setup correctly you will have access to a choice of front ends, latest mame and rom set... choice of emulators too.

 

[dee2eR]

[EDIT] Fixed. Dee should be able to send and receive PMs now so might be worth resending any that have already been sent. I don't have time right now to look into if any are waiting or not.

Thanks for doing this for me.

I don't believe any PMs that were tried got through.

Anyone who has tried to PM I think it should work if you try again. Please be aware I have recieved a lot of interest this week so if it takes a day or two to respond to your message I apologise.

 

[swisstoni]

New videos added to the original post showing CPS1, CPS2 and Street Fighter 3rd Strike on CPS3

 

[vib_ribbon]

New videos added to the original post showing CPS1, CPS2 and Street Fighter 3rd Strike on CPS3

very nice! the picture dont look so shoddy at all despite no video amp.

how long does it take from power up to get to the menus?

 

[RGP]

I'm with Colin here and interested in working on a 240p solution for 15k direct on the board but i'd very much like to get one of these after xmas to experiment with.

I've bought a number of dev kits to play with for no other reason than to see what they can do and naturally this is one which has legs for all of us.

 

[corn]

Nice work dee2eR - its a great, neat, little solution.

I've had a read through your posts on aussiearcade and was hoping to get my existing Pi hooked up to my Astro City. I've grabbed a copy of your SD card image and wired up my Pi/HDMI-VGA adapter to the RGB connectors on a little SONY PVM Monitor. I know the PVM works fine as I've been using it hooked up to a JAMMA board. However, I'm not having much luck - just garbage on screen.

Looking at your post, I'm guessing I'm hitting one of two issues:

1) The HDMI -> VGA (which ISN'T the active type with a USB port) is the wrong type

2) I have sync issues.

I've ordered what looks to be an identical (from the outside!) HDMI->VGA adapter, I'll try that when it arrives.

You mentioned in your posts "....set the pi to low res and combine the h and v sync."

I've tried simply combining (soldering the H-SYNC and V-SYNC) cables together, this didn't work. Do I need something like the "Dodgy Diode" circuit mentioned here?

http://members.optusnet.com.au/eviltim/scart.htm

Thanks in advance!

 

[RGP]

I don't know much about your Astro city cab and its monitor (is it VGA or 15khz in those?) but I do run into this sync combine issue a number of times.

I've had intermittent luck just twisting the H+V together, additionally you could be getting positive sync out of the HDMI->VGA and need negative sync at the Astro City monitor.

A number of monitors will give you the "I don't care its a sync signal" approach but some are petty and want it a particular way.

JAMMA is usually negative composite sync.

If this is the problem then you can create the correct circuit by using a 74LS86 (XOR gate).

Pin 1 - H input

Pin 2 - V input

Pin 3 - connect to pin 5 (output of the two signals XOR'd together)

Pin 4 - +5v (add a 1k resistor in series if you think necessary)

Pin 6 - output to monitor sync in composite negative

Pin 7 - GND

pin 14 - +5v

What its doing is taking the H + V and XOR'ing them together, the output will be positive, you can then feed it through another XOR using HI as an input reference along with the signal and it'll come out inverted (negative) at the other side on pin 6.

This is the same as using an LS86 to combine the signals and then an LS04 to invert the final output.

I'm not saying that's the solution but it might be on the right track.

 

[corn]

I don't know much about your Astro city cab and its monitor (is it VGA or 15khz in those?)

Its 15khz (Nanao MS8-29 if I remember correctly). I've not actually tried the Pi in the astro as a) I didn't want to screw the monitor up b) its in a cold garage and won't be powered on for a while.

I guess I was naively thinking that if I could get it working on the PVM that it would just work on the Astro (and vice versa). Cheers for the details of the circuit, I'll have to look into that if the HDMI-VGA adapter I get doesn't work.

 

[simonden]

I don't know much about your Astro city cab and its monitor (is it VGA or 15khz in those?) but I do run into this sync combine issue a number of times.

I've had intermittent luck just twisting the H+V together, additionally you could be getting positive sync out of the HDMI->VGA and need negative sync at the Astro City monitor.

A number of monitors will give you the "I don't care its a sync signal" approach but some are petty and want it a particular way.

JAMMA is usually negative composite sync.

If this is the problem then you can create the correct circuit by using a 74LS86 (XOR gate).

Pin 1 - H input

Pin 2 - V input

Pin 3 - connect to pin 5 (output of the two signals XOR'd together)

Pin 4 - +5v (add a 1k resistor in series if you think necessary)

Pin 6 - output to monitor sync in composite negative

Pin 7 - GND

pin 14 - +5v

What its doing is taking the H + V and XOR'ing them together, the output will be positive, you can then feed it through another XOR using HI as an input reference along with the signal and it'll come out inverted (negative) at the other side on pin 6.

This is the same as using an LS86 to combine the signals and then an LS04 to invert the final output.

I'm not saying that's the solution but it might be on the right track.

The less fun alternative is to buy an Extron RGB160xi and just plug it in.