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Chihiro Lindbergh Linkup

bobbydilley

bobbydilley

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I’ve recently bought a Chihiro and was playing outrun 2 SP when I thought about the network play option.

Both the Lindbergh and the Chihiro have the network play option and from what I’ve gathered the Lindbergh game is a port of the chihiro one.

So my question is has anyone ever tried connecting those 2 games together?

I would think it if doesn’t work it’ll just have some little bit of protocol to stop them working together or purpose, but I think it shouldn’t be too hard to sniff the packets and convert them to work together?
 
There likely will be a version check in the game code. The chihiro changes it's ip to some fixed value once the game starts.
This could be tricky for packet sniffing as a good switch should only sent the data out on the port with the other device. So, you either need a good old fashion hub that sends it's network traffic to all ports or you need a managable switch.

I wonder if they have used the system link libraries that xbox was using.
If that's the case, an xdk might contain some valid information about the packet structure.

It's also possible they use a system comparable to the optical networking that was used with model 3 and model 2 boards.

Little is known about chihiro networking. It creates a drive partition and has a number of control registers on the LPC bus, but that's pretty much it.
Mame just emulates some standard responses to keep the programs happy. (It's better than nothing). It only emulates type 1 (with the regular netdimm) and not the type 3.
 
I've got a Microtik Routerboard which supports all the necessary stuf you need to sniff out packets, so should be okay!

I'm hoping that the connection code isn't based on anything to do with the OS, and is just ported from the Chihiro strait to the Lindbergh, with maybe a digit to stop them working together.

When you say ' It only emulates type 1 (with the regular netdimm) and not the type 3.', are you talking about the Media Board? The networking runs from the seperate LAN port that isn't on the media board for connecting games together I thought?
 
left is type 3, right is type 1...
 

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Thank you for the images, but I fully understand what a Type 1 and Type 3 are. They are the same consoles, with a different board attachment on top so you can either fit a Net Dimm, or use the Type 3 media board as it is.

The media board (I believe) has absolutely nothing to do with the game linking, which is from the LAN Port coming from the Xbox part of the console. The only two games for the Type 1 system (Crazy Taxi High Roller + The House Of The Dead 3) didn't actually support link play, and so I don't think we need to get distracted looking at the two types of Chihiro.

At some point, I will do a cursory connection of the Lindbergh + Chihiro versions and see if they make any attempt to talk to each other and will update the thread when I do.
 
linking is from the lan port on the option board. The LAN C core port is not used for linking, as far as I understand.
 
bobbydilley said:
At some point, I will do a cursory connection of the Lindbergh + Chihiro versions and see if they make any attempt to talk to each other and will update the thread when I do.
Click to expand...
Confucius say, empirical evidence is best evidence.
 
Indeed, the lan port of the main board in the bottom box isn't used for game linking. Chihiro type 3 has 2 additional boards in the upper box. One is the dimm board and the other is the network board. The same network board is used on a triforce type 3.

The chihiro type 1 has one additional board in the upper case I seem to remember it's called the media board. You can plug a normal dimm or netdimm on that media board. That netdimm has the network port used for netboot. (And eventually game linking altough no linked games came out for the model 1)

So, when segaboot.xbe is running. (The dashboard that is showing the chihiro splash screen and also contains the main test menu) it communicates with the dimm board. The way this is done differs between the type 1 and type 3. The one mame is emulating is the type 1.

Sega model 2 and model 3 used a separate networking board (using optical fibers to transfer packets) It had a common memory region with the main processor and network traffic was initiated by reading and writing to that region. The chihiro has a partition on the dimm emulated drive "mbcomm" Those partitions are also accessible by both the dimm board and the main board. This resembles a bit how things where done before. Even naomi has a communication board that was using optical fibers.

How networking works exactly under the hood is not yet known I assume. I was able to reverse the base board usb communication so I can use the JVS controls, but I have no idea about the networking. Linking multiple homebrew chihiro programs is still out of reach. Since I can use the other main board network port for that, it's not a high priority issue.
 
Thanks for clearing that up guys, sorry for my confusion!

So on the settings we’ve got the Media Network and the Core Network.

I’ve only got 2 Network ports on my chihiro, one is the LAN C port which we’ve decided isn’t used. And the other is on the media board used for Netbooting.

Are we saying this top Ethernet port used for net booting is also used for linking games?
 
Exactly. Core network isn't used by chihiro games. Some games even change the network port ip when they are running. There are some discussions about it on this forum.
 
Thanks for all the info - I'll look into all of that.

Changing the IP might be the first issue, as it could be that the static IPs that are set are different on the Lindbergh/Chihiro. The other post shows how to change the Chihiro's forced assigned IP so i'll make sure to line it up with the Lindberghs IP first.
 
That sounds like a good idea. Keep us updated. Interested to see what you find.

I'd jump in on this with you, but my lindbergh is not running right now. If I get it working I'll see if I can dig into it also.
 
So as a first go, it doesn't work. Both just sit there saying checking network for ages.

The setup is as follows:

Outrun 2 SP DX on Sega Lindbergh Multi with Lan cable coming from the Lan port on the motherboard (not the PCI card) to a switch.
Outrun 2 SP on Sega Chihiro with Lan Cable coming from Media Board Lan Port to a switch.

Tried in both configurations and it doesn't work, not even sure if ethernet on the Lindbergh is being accessed. Time to bring out my Routerboard and packet sniff!
 
You could check the lindbergh manual for outrun to see what network adapter you are supposed to use for linking multiple units.
It's one unknown less to worry about.

It could be interesting to have 2 chihiro or lindberghs to sniff the traffic between them.
 
Yep I’ll have a look - although no lights came on on the PCI Ethernet card so I’m not even sure it’s really an Ethernet port.

If there is anyone else in the UK with one I’d be more than happy to meet so we could try it out
 
I've been looking into the Lindbergh side of things, here's a few of the things I've noticed:

- Outrun broadcasts to the entire subnet (255.255.255.0) via UDP port 10600.
- If you give the Lindbergh a static IP address, it assumes the other players are at the next IP address in the range. For example, if you set it to be 10.0.0.20, it will assume the player 2 device is at 10.0.0.21, player 3 at 10.0.0.22 etc. However it will still broadcast rather than communicate directly.
- I suspect broadcasting is used so all players (there can be a max of 4) get updated at the same time.
- The broadcast packet is always 1248 bytes in size.
- The packet is "protected" by a CRC.
- The packet includes the game ID. This would clearly cause problems between a Chihiro and Lindbergh link.
- The packet includes a bunch of info about the cabinet. So for example, you can't link an UPLIGHT (haha) against a DX cabinet.
 
@doozer You never fail to amaze me with how knowledgeable you are!

In terms of IP the chihiro is similar - it sets its own up to 192.168.72.player where player is which node you are starting from 1.

We will somehow have to modify the game I’d which may be an issue, as I don’t know what else uses that.

I’ll packet sniff the chihiro soon and upload a dump of that
 
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