Main > Main Forum
Suzo- Happ PC Arcade Spinner? Plug and Play?
FrizzleFried:
--- Quote from: RandyT on February 28, 2009, 02:50:47 am ---
--- Quote from: TPB on February 28, 2009, 02:36:19 am ---Bender has been wrestling with the TT-HL's incompatibility with his 64 bit OS.
--- End quote ---
It works fine, so apparently it's not incompatible. And the solution is not an "OS patch". It's just a piece of software that the crazy 64-bit MS OS makes you jump through a few more hoops in order to use. Lot of folks on the web have been using it and do so without crippling their systems. Stuff happens, but not all of the time, and not to everyone.
--- Quote ---No doubt we'll see USB 2.0 versions of the TT2 and TT-HL in the future.
--- End quote ---
Unlikely. As I have already stated in a different thread, I won't sacrifice compatibility with the huge number of USB 1.1 systems out there in order to accommodate the relatively microscopic number of 64 bit users in this market, especially when a widely used software solution exists which can actually outperform the "out of the box 2.0 only" approach.
RandyT
--- End quote ---
My understanding was the USB 2.0 is backwards compatible with USB 1.1 in that if you plug a USB 2.0 device in to a USB 1.1 hub or port that the USB 2.0 device will act like a USB 1.1 device? How is including USB 2.0 compatibility sacrificing compatibility if this is the case?
Derrick Renaud:
--- Quote from: Bender on February 28, 2009, 12:22:53 pm ---so if I understand the problem, it is that there is too much data being thrown at windows to handle at 125Hz
so if you have a regular resolution spinner wouldn't that be less data being sent, and wouldn't that explain why a standard resolution spinner works fine under the 125Hz windows standard?
--- End quote ---
A hi-res and lo-les spinner should both have the same issue with windows locked at 125Hz. But you have to remember, they both have to be scaled so they turn at the same full turn count rate as the original game. Let's stick with Tempest. We know that a 1200 count hi-res is 300 optical counts times the 4 edges counted by the IC. And that it should be set to a MAME analog sensitivity of 6% to match the 72 count of the real game control.
A lo-res spinner has 24 optical counts. I'm sure there are others, but let just use this as an example. Now we times this by 4 edges counted by the IC. This gives a resolution of 96. So 72/96 = .75 or 75% MAME analog sensitivity.
Both spinners should now have the same backspin when locked at 125Hz poll rate. Remember as I have previously shown, the Hi-Res 1200 count spinner will not overflow at 125Hz until you manage to spin it over 13 revolutions per second. Good luck trying.
The problem here is realizing that there is the windows poll rate and the original game's poll rate. The supplied windows polled data is scaled by the MAME sensitivity before it is polled by the emulated game. So if both hi and lo res spinners are set as I described, and both spinners are polling at the windows 125Hz rate, and you spin both the same, then the emulated game receives identical data. Except the movement/data will be smoother with the hi-res spinner.
The problem is 125Hz is half of the game's poll rate. And as the game only uses a 4-bit counter, it will easily overflow because the game receives a value of 0 for the first poll, because windows has not supplied new data. Then the game receives the total of 2 of it's expected polls at it's next poll. So in effect the game can accept a change of 15 on each of it's polls before it rolls over, but windows is limiting this to 7. Sorry I can't explain it any simpler then that.
Actually I think I might be beginning to understand why people think lo-res is better for not having backspin. I think people are taking their 96 resolution spinners and setting the MAME analog sensitivity to 25% or so and saying, "Hey, now it does not backspin. I fixed it!"
That is not the case. If you are setting it to anything lower then 75%, you are in effect gearing the spinner down. At 25%, you are now spinning the control 1/3 the speed of the original control and not moving as fast as the real control would spin. If you set the 1200 hi-res spinner to 2%, they would now both be behaving the same again. But you did not fix the backspin issue. You are only masking it by turning slower.
Lets put this another way. If you hack the ROMs in the original game, tell it to always use a data of 0 for the first sample and then use the accumulated value of 2 samples for the second sample, then the original game (not emulated) would have the same backspin issue as we are seeing in an emulated game with a poll rate of 125Hz.
Someone is going to have filter all the info I've supplied in the 3 different spinner topics where we have been discussing this issue and turn it into readable lay-english for the wiki. ;D
D.
RandyT:
--- Quote from: FrizzleFried on February 28, 2009, 01:38:55 pm ---My understanding was the USB 2.0 is backwards compatible with USB 1.1 in that if you plug a USB 2.0 device in to a USB 1.1 hub or port that the USB 2.0 device will act like a USB 1.1 device? How is including USB 2.0 compatibility sacrificing compatibility if this is the case?
--- End quote ---
This is not always true. I have seen instances of where even the *backward* compatibility of some 2.0 systems has not worked as expected, and required a change in the firmware to accommodate it, where that same device worked flawlessly on a 1.1 system.
One might be able to get around things by using a 2.0 hub on a 1.1 system and let the hub do the re-negotiations, but at that point, you might as well install a new USB card.
RandyT
Derrick Renaud:
BTW, to diverge a little, the whole optical encoder (tooth) count being counted on each of the 4 edges by modern encoder ICs is the reason most trackballs need to be scaled using a MAME analog sensitivity of 25%.
If your trackball is the same size as the original trackball and has the standard 24 teeth, then it needs to be scaled to 25%.
D.
RandyT:
--- Quote from: Derrick Renaud on February 28, 2009, 02:16:09 pm ---BTW, to diverge a little, the whole optical encoder (tooth) count being counted on each of the 4 edges by modern encoder ICs is the reason most trackballs need to be scaled using a MAME analog sensitivity of 25%.
If your trackball is the same size as the original trackball and has the standard 24 teeth, then it needs to be scaled to 25%.
--- End quote ---
Interesting. Someone should probably tweak that one somehow as well. Regular 24 tooth trackballs are poor when you try to use them as a mouse because they go so slow. This makes upping the hardware resolution very attractive, which would require lower sensitivity settings. And one thing MAME lacks severely, is tweakability at the low end of the sensitivity scale. How about adding some tenths to the sensitivity settings? Not very useful at the +100 levels, but very useful below.
RandyT