Viewing Issue Advanced Details
ID Category [?] Severity [?] Reproducibility Date Submitted Last Update
07941 DIP/Input Minor Always Apr 14, 2021, 13:14 Apr 14, 2021, 14:03
Tester dink View Status Public Platform MAME (Official Binary)
Assigned To dink Resolution Fixed OS Windows Vista/7/8 (64-bit)
Status [?] Resolved Driver
Version 0.230 Fixed in Version 0.231 Build 64-bit
Fixed in Git Commit f733062 Github Pull Request #
Summary 07941: omegrace: Omega Race p2 inputs (coctail) scrambled
Description Omega Race p2 inputs (coctail) scrambled
Steps To Reproduce put into coctail mode via dips
play game with p2, observe that rotating ship is glitching
Additional Information Solution:

static const uint8_t spinnerTable_p2[0x40] = {
0x00, 0x01, 0x05, 0x04, 0x06, 0x07, 0x17, 0x16,
0x14, 0x15, 0x11, 0x10, 0x12, 0x13, 0x1b, 0x1a,
0x18, 0x19, 0x1d, 0x1c, 0x1e, 0x1f, 0x3f, 0x3e,
0x3c, 0x3d, 0x39, 0x38, 0x3a, 0x3b, 0x33, 0x32,
0x30, 0x31, 0x35, 0x34, 0x36, 0x37, 0x27, 0x26,
0x24, 0x25, 0x21, 0x20, 0x22, 0x23, 0x2b, 0x2a,
0x28, 0x29, 0x2d, 0x2c, 0x2e, 0x2f, 0x0f, 0x0e,
0x0c, 0x0d, 0x09, 0x08, 0x0a, 0x0b, 0x03, 0x02 // p2 table decoded by dink (fbneo) aug.2020

uint8_t omegrace_state::omegrace_spinner2_r()
return (spinnerTable_p2[ioport("SPIN1")->read() & 0x3f]);

void omegrace_state::port_map(address_map &map)
map(0x16, 0x16).portr("SPIN1"); /* 2nd controller (cocktail) */
map(0x16, 0x16).r(FUNC(omegrace_state::omegrace_spinner2_r)); /* 2nd controller (coctail) */
Github Commit
Regression Version
Affected Sets / Systems omegrace
Attached Files
zip file icon (443 bytes) Apr 14, 2021, 13:16 Uploaded by dink
source chunk
There are no relationship linked to this issue.
User avatar
Apr 14, 2021, 13:26
in service mode, p2 input binary counter counts normally before this descramble table, this is probably what lead the original developer to think the p2 coctail inputs were OK (re: notes in driver)

best regards,
- dink