Sega-Naomi

OldFoo · Post by **OldFoo** » Mon Jun 18, 2007 7:35 am

Well I am sure that it is USB compliant, and I can't see Lindbergh having a dedicated USB port, as far as I know, the I/O will work no matter what USB you plug it into on a Lindbergh (remember operator's are thick!)

OldFoo · Post by **OldFoo** » Mon Jun 18, 2007 1:47 pm

Haha! Yeah, thick is right!

Also something to take note, serial connections such as RS232 AND RS422 cannot be daisy-chained like USB can. They are single 'client' to 'host' connections.

OldFoo · Post by **OldFoo** » Tue Jun 19, 2007 7:27 am

joshua3dg wrote:I see what you are saying, but if that's true, then hooking up the I/O to a computer's USB port should do nothing. In fact, you get a 'New hardware found' message, but no driver is available.

Well, if it's not a USB device you don't get anything at all because the device never attaches itself to the OHCI/UCHI/ECHI controller.

joshua3dg wrote:As for the JVS Standards book, I've went through the trouble of translating it, but it doesn't give any more information than we already know. It just lays it out in detailed specifics. It doesn't mention or describe the protocol in of itself.

Perhaps we had different documents, the documents I had contained some of the electrical characteristics of the signaling, however I couldn't read it enough to know if it had any actual protocol information as far as the bytestream was concerned.

AndyGeezer wrote:Well I am sure that it is USB compliant, and I can't see Lindbergh having a dedicated USB port, as far as I know, the I/O will work no matter what USB you plug it into on a Lindbergh (remember operator's are thick!)

That's odd, does the Lindbergh have any other "Real USB" devices that plug into those ports? (ie: ones that can also be plugged into a PC)

joshua3dg wrote:Haha! Yeah, thick is right!

Also something to take note, serial connections such as RS232 AND RS422 cannot be daisy-chained like USB can. They are single 'client' to 'host' connections.

Well like I said, it wasn't RS422 but it seemed to be it's own proprietary signaling protocol. The big difference was in fact that it had an arbitration signal to allow multiple devices on one port to communicate.

If it's of a lot of interest to people I can dig up my documentation again and get some more specific information... the reason I had interest in it myself is because I actually began a project to write an "OpenJVS" library to handle the protocol in raw packet format from USB.

However after some preliminary work and realizing that the JVS Io boards I had would not even associate with my USB stack I did some further digging and found out that it didn't seem to be real USB at all.

(I'm actually using FreeBSD UNIX, not windows... and since I actually did some of the work on the USB stack there I have pretty direct access to the USB system internals - so I can assure you it wasn't a lack of driver or etc because I still would have been able to attach the device enough to pull up it's USB descriptor and so on.)

I suppose if I completely misunderstood the JVS documentation it could have been a USB host device (the Io Board that is...) however that would make the Naomi/Lindbergh/System 2(4/5)6 a "USB Device" (Like a PSP or digital camera is) and would still render it incompatible with normal USB devices.

Just for fun I can do some experimenting again this weekend, but I'm still pretty sure it's not actually USB at the electrical/signaling level.

OldFoo · Post by **OldFoo** » Tue Jun 19, 2007 11:19 am

AndyGeezer wrote:Well I am sure that it is USB compliant, and I can't see Lindbergh having a dedicated USB port, as far as I know, the I/O will work no matter what USB you plug it into on a Lindbergh (remember operator's are thick!)

the DVD-ROM drive is USB and yep it will work on a regular PC.

Also the Lindbergh uses the same GD type power cable to power the DVD drive.

I agree the I/O board is not standard USB protocol, it is more a serial protocol.

Obviously Sega R&D have managed to get it to function on a PC USB bus.

The pinout is

1Sense

2Data+

3Data-

4Gnd

It is not a powered hub, hence it needing +5V on the I/O boards, no doubt Sega are using a custom ATX motherboard with some auto-switching USB connector to tell the difference bewteen JVS Serial and USB P'n'P

So I revoke my statement is saying it is USB compliant! I am the Geezer and I can do that.. :smt019

OldFoo · Post by **OldFoo** » Wed Jun 20, 2007 11:23 am

Okay, I can confirm the following:

Lindbergh has 2 types of USB ports

USB 2.0 (like PC)

JVS Serial USB

So JVS I/O goes into the JVS Serial USB ports while standard USB 1.1/2 can go into the other USB ports.

Lindbergh is basically a customised PC mainboard as it has JVS serial and Security PIC support.

OldFoo · Post by **OldFoo** » Wed Jun 20, 2007 11:49 am

AndyGeezer wrote:Okay, I can confirm the following:

Lindbergh has 2 types of USB ports

USB 2.0 (like PC)

JVS Serial USB

So JVS I/O goes into the JVS Serial USB ports while standard USB 1.1/2 can go into the other USB ports.

Lindbergh is basically a customised PC mainboard as it has JVS serial and Security PIC support.

Ok, that makes sense :)

I expected it had a dedicated port for the JVS plug, as it's quite different from USB electrically.

Also, that "sense" pin on the JVS is what it uses to negotiate multiple daisy chained devices on the same bus, which is something that USB does not do.

Thanks for the clarification on Lindbergh... I think we can put the myth that JVS has anything to do with USB besides using a USB cable to rest at last. :)