Sounds good to me, great stuff
I'm still catching up. I've managed to get mame built from github and I can run hard drivin' (compact) and airborne. I've just not hacked the code yet (But I think that's what I need to do to get a feel for what is happening). I'll start experimenting with my wheel at the weekend.
Something that has always bugged me with the compact roms, is that it is not possible (yet, I think) to successfully calibrate the wheel using the service menu. I went and did some reading/investigation, trying to work out what values to expect (When viewing the "Control Inputs" service menu) from a successfully calibrated wheel. I didn't get very far. Thought I'd post my notes as they might be of interest/help:-
Compact harddrivin service manual (HDC_TM-329_2nd.pdf):
041787-02 Steering Encoder Disk.
043807-02 Centering Encoder Disk.
HDC_TM-329_2nd.pdf, From the "Control Inputs" service menu:
As you turn the steering wheel clockwise, the hexadecimal number should increase and change to zero once every turn.
As you turn the wheel counterclockwise, the number should decrease. Everytime the steering wheel passes the center position,
the words center edge should change from blue to green.
HDC_TM-329_2nd.pdf, from a section near the end about installing a new encoder wheel:
Install the steering wheel with the center spoke down. Make sure the single hole on the centering disk is between the opitcal reader on the centering
PCB so the steering wheel will be correctly centered.
From the Race Drivin' Compact Manual, for the Main Board Memory Map, it says:
OPTO: Optical Steering Wheel Reader
400000 (R) OPTORD Read the Optical Counter
404000 (W) OPTORES Reset the Optical Counter
408000 (W) CENRES Reset the Optical Centre Flag
I found a picture of a 041787-02 Steering Encoder Disk, and counted 72 holes. Based on this, I don't think we should see a steering value (When viewing the "Control Inputs" service menu) reported that exceeds 72 (Or maybe 144 if we are counting teeth passing as well has holes). Thus, when turning clockwise you'll see 0 increase to 72 then back to 0 etc... When turning anticlockwise you'll see 72 decrease 0 then back to 72 etc... In mame, I think we see values much greater than 72, this might cause strangeness. I think I'll try and hack things so that I force these 'ideal' values to occur at calibration.
Something odd I noticed, is that in mame when viewing the "Control Inputs" service menu and turning the wheel clockwise, I see the hexadecimal number decrease, not increase...