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Irken (MiSTer) JAMMA Expander

aerobert said:
Bought myself a mistersetup with Revision 1 of the expander. Looking forward to jump into this new landscape of both mister and expander.

The lack of USB (and therefore wifi) makes me scratch my head how to set this thing up since I don't have anything using RJ45 LAN anymore. :dead: Not even my slim laptop has one. Maybe an ugly solution is the external USB hub people in this thread has used. Any hub in particular that's good?

Also a question to @invzim, what is the design philosophy behind the usage of HDMI interface between the devices instead of taking 240p from the GPIO? I assume one of the reasons is to keep the possibility to use dual ram?
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New rev has USB hub - you could always connect usb wifi to do updates, then reconnect the expander - not optimal though..

There are a myriad of reasons behind the design choices made, ESD protection, user errors, ease of installation, clean design etc etc, but the bottom line for users would be that more colors are better. Not many games use 24 bit color, but even if it only has 512 colors total - you want to the output to be the right colors. With more bits, the accuracy increases.
 
Yeah, the ram slot was the obvious thing for me. Futureproofing is great!

As mentioned I bought a used setup with REV1 so I think I will just go ahead and buy the USB hub board and add a bluetooth and wifi dongle in order to go wireless with both keyboard and wifi.
 
Looking for a short HDMI cable with two 90 degree angled connections to make the REV1 installation a bit more compact.

Can anyone recommend a good product? I don't find many (or any) options...
 
Oh I see! Thanks for the tip. Now to decide whether a right-right or a right-left works best. :D
 
alamone said:
I added an official MiSTer USB hub and right/left angle HDMI cable, stuffing most of the wires under the DE10-nano. I also played a quick round of 1941 and I didn't notice any issues with stuck inputs.

IMG_2669.jpg
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I decided to do the same and bought Ricardos usb hub board but realized late the USB bridge occupies the micro b socket from the expander otg. Doh.

What cable do use now instead from the expander? Should one go for a Micro B female to A adapter along with the original cable provided? Or just a USB female to male extender? (Is it otg?)

Maybe @invzim can answer that best?
 
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I recently picked up a MiSTer and an Irken Jamma Expander. They're both amazing things, but I'm super impressed with the Irken board and all its thoughtful features. Tons of lights, switches and a little display that's already helped me solve two power problems (one PSU was 5.2V, and one would only drive enough 5V if the 12V was also loaded).

But, and I think this is a common lament, the controls are driving me mad. I can't use the JAMMA control inputs for just about anything. Most arcade cores ignore the service button (and I don't have a coin button wired in yet). Some games work just fine this way, but I can only test the ones that don't need more than the onboard RAM 'cause my f**king RAM board is sitting in a container somewhere. (ノ°Д°）ノ︵ ┻━┻

But I also can't play any console games with the JAMMA inputs. Neither the PC Engine or MegaDrive core have a functioning START button. It registers just fine on the Irken screen, but the console cores ignore it. The joysticks register fine, I can maneuver through menus without issue, I just can't start a game. All controls work fine if I plug a USB controller in, but that defeats a lot of the reason for the JAMMA board.

So, I ask you all - am I doing something wrong?

Any tips, clues, links or suggestions are welcomed.
 
NFGx said:
I recently picked up a MiSTer and an Irken Jamma Expander. They're both amazing things, but I'm super impressed with the Irken board and all its thoughtful features. Tons of lights, switches and a little display that's already helped me solve two power problems (one PSU was 5.2V, and one would only drive enough 5V if the 12V was also loaded).

But, and I think this is a common lament, the controls are driving me mad. I can't use the JAMMA control inputs for just about anything. Most arcade cores ignore the service button (and I don't have a coin button wired in yet). Some games work just fine this way, but I can only test the ones that don't need more than the onboard RAM 'cause my f**king RAM board is sitting in a container somewhere. (ノ°Д°）ノ︵ ┻━┻

But I also can't play any console games with the JAMMA inputs. Neither the PC Engine or MegaDrive core have a functioning START button. It registers just fine on the Irken screen, but the console cores ignore it. The joysticks register fine, I can maneuver through menus without issue, I just can't start a game. All controls work fine if I plug a USB controller in, but that defeats a lot of the reason for the JAMMA board.

So, I ask you all - am I doing something wrong?

Any tips, clues, links or suggestions are welcomed.
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I would
1 - wait for your sdram module, all the 'good' cores require it and will work out of the box with the Expander, or
2 - read though this https://irkenlabs.com/jamma-expander/operation-gamepad/ , then it will work like the 'other' adapters.
 
invzim said:
I would
1 - wait for your sdram module, all the 'good' cores require it and will work out of the box with the Expander, or
2 - read though this https://irkenlabs.com/jamma-expander/operation-gamepad/ , then it will work like the 'other' adapters.
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RAM arrived. I am super happy with this thing.

Is there any way to make it work on a 'normal' VGA monitor with normal levels though? My Naomi Universal Cabinet has a 31kHz monitor but it wants VGA-level, not JAMMA-level signals.

I assume there's no video amp bypass. Is there a preferred or suggested method for dealing with the RGB from the Expander?
 
I am pretty sure you can just set it to output 31K:
https://irkenlabs.com/jamma-expander/expander-user-interface/

You may need to also edit the setup/settings ini file for the MiSTer, but I have never messed with this setting on the Expander, YMMV but zim has built a lot of safeguards into the SyncGuard to prevent most scenarios where you could potentially mess something up by sending the wrong video signal.
 
kazuo said:
I am pretty sure you can just set it to output 31K:
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Oh yeah, it's possible. I've never tried it but the option does exist.

My issue is with the RGB signal voltage. JAMMA is 3V, VGA is 0.7V.
 
Right, I am pretty sure that can be changed in the MiSTer .ini directly.

https://mister-devel.github.io/MkDocs_MiSTer/basics/video/#video-presets - video mode 6. Unsure if this is supported or not through the Expander, but... only one way to find out? If it doesn't come through the JAMMA edge, I think you can probably just grab it from the HDMI out using HDMI to VGA cable?
 
kazuo said:
Right, I am pretty sure that can be changed in the MiSTer .ini directly.
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I'm more than happy to be wrong about this, but I think you're talking about the resolution, and I'm talking about the voltage. The low-res JAMMA arcade monitors the Irken board is designed for use more volts, the Naomi VGA-resolution monitor uses standard VGA volts.
 
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NFGx said:
RAM arrived. I am super happy with this thing.

Is there any way to make it work on a 'normal' VGA monitor with normal levels though? My Naomi Universal Cabinet has a 31kHz monitor but it wants VGA-level, not JAMMA-level signals.

I assume there's no video amp bypass. Is there a preferred or suggested method for dealing with the RGB from the Expander?
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You assume correctly, it's only JAMMA level rgb out. For a Naomi Universal cabinet, the JVS Expander would be a better fit.
 
invzim said:
You assume correctly, it's only JAMMA level rgb out. For a Naomi Universal cabinet, the JVS Expander would be a better fit.
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Thanks for that. Probably any further discussion about this will be way off topic for this thread.

Now that I think about it... For any other device I'd put in there, I'll either have the right levels already (consoles) or the XRGB will take care of it. So...

@invzim - Since the only JAMMA device I expect to run in the Naomi is your JAMMA Expander, can you suggest some way to bring those levels back to VGA standard? I mean I COULD pick up one of your JVS Expanders, but that seems like a very expensive solution and swapping the DE10 from one device to the other all the time would be a hassle.
 
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NFGx said:
Thanks for that. Probably any further discussion about this will be way off topic for this thread.

Now that I think about it... For any other device I'd put in there, I'll either have the right levels already (consoles) or the XRGB will take care of it. So...

@invzim - Since the only JAMMA device I expect to run in the Naomi is your JAMMA Expander, can you suggest some way to bring those levels back to VGA standard? I mean I COULD pick up one of your JVS Expanders, but that seems like a very expensive solution and swapping the DE10 from one device to the other all the time would be a hassle.
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You could pick up a jammafier rev 2 that will re-amplify to 75-ohm vga levels but I presume your Naomi Universal is no longer JVS?
The A1 scaler is also an option, but a little kludgy as the MiSTer does perfect line-doubling internally.
You can also experiment with adding series resistors on the RGB lines, perhaps around 200 ohms.
The last option is to remove/bypass the video amplifiers by doing a bit of micro soldering on the expnader itself. Or find a device that attenuates JAMMA video to scart/VGA levels, I no longer make the Tri-sync helper that did this as it's embedded in the rev 2 jammafier.
 
I have a strange problem, it seems every 2-3 times I power up my cab with the Jamma expander connected the unit powers on for a few seconds gets to the mister menu, and then the expander powers itself off. If I power cycle it usually comes back up fine. I've checked my voltages and updated the firmware, I assumed that may be the problem, but it still happens pretty often.

Once it is on and working, I have no problems. It's only an inconvenience to power cycle it a couple times.
 
Would HDMI to VGA using direct_video not output 0.7v VGA video signal? Seems weird that it wouldn't, don't people just hook such setups straight up to consumer VGA displays? I suppose you could just attenuate it yourself if you're motivated enough to just "make it work", seems like enabling the scandoubler and measuring the video output on the HDMI to VGA end of the cable is the place to start. It's entirely possible I am totally off-base on this, I'm just making assumptions based on the MiSTer documentation. This post and this post seems to suggest it should work.. but YMMV and all that. As you might already know, measure the voltage first.

OR you could just buy a JVS Expander, like zim suggested earlier.

Metal Slug said:
I have a strange problem, it seems every 2-3 times I power up my cab with the Jamma expander connected the unit powers on for a few seconds gets to the mister menu, and then the expander powers itself off. If I power cycle it usually comes back up fine. I've checked my voltages and updated the firmware, I assumed that may be the problem, but it still happens pretty often.

Once it is on and working, I have no problems. It's only an inconvenience to power cycle it a couple times.
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I have a weird issue sometimes where the Expander/MiSTer will boot to an empty menu, with no games found. Power cycling a couple times usually fixes it. I can't reliably reproduce the problem.
 
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