03142: All drivers using PORT_CHANGED callbacks: Input port callback functions are not triggered correctly during INP playback.

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
03142	DIP/Input	Major	Always	May 4, 2009, 10:39	Dec 28, 2009, 10:26

Tester	mahlemiut	View Status	Public	Platform	MAME (Official Binary)
Assigned To		Resolution	Fixed	OS
Status [?]	Resolved			Driver
Version	0.131	Fixed in Version	0.136	Build	Normal
		Fixed in Git Commit		Github Pull Request #

Summary	03142: All drivers using PORT_CHANGED callbacks: Input port callback functions are not triggered correctly during INP playback.
Description	When playing back INPs in MAME or MESS from drivers that use PORT_CHANGED callback functions, they are not triggered by input from the INP file. Instead, they are still triggered by normal input. For example, in Zaxxon, you can insert coins while recording, as normal. But on playback of the resulting INP, coins are not registered unless you again press 5. No normal inputs should be accepted during INP playback.
Steps To Reproduce	Record an INP (use mame zaxxon -record test.inp). When emulation starts, insert a few coins, and exit MAME. Playback the INP again (use mame zaxxon -playback test.inp). You will not see any coins inserted, as you would expect. You can insert coins during playback by pressing 5, which should not happen.
Additional Information	This behaviour was first noted in the MESS Amiga driver, where the keyboard doesn't appear to work on INP playback. I believe it was determined that the keyboard inputs are recorded in the INP file, just not used on playback. It was initially thought to be local to that driver, until I tested the Neo Geo Pocket driver, which did the same with just the power button (other controls worked fine on playback). The power button input was the only input with a PORT_CHANGED callback, which pretty much confirmed these callbacks as not working on INP playback correctly. I checked through the current MAME source, and found 28 drivers that use these callbacks, mostly for coin inputs. I tested both Zaxxon and Ladybug to confirm for sure that it is a MAME issue.
Github Commit

Flags
Regression Version	0.125u3
Affected Sets / Systems	All drivers using PORT_CHANGED callbacks

Attached Files	inputport-281209.diff (835 bytes) Dec 28, 2009, 01:48 [Show Content]

No.04315 Tafoid Administrator May 4, 2009, 13:53 edited on: May 4, 2009, 13:54	Good catch. Using Ladybug and Zaxxon, I confirmed the behavior. I also narrowed down regression to 0.125u3. Added a PORT_CUSTOM for the eeprom bit reading. Updated several drivers to use that by specifying it in their input ports instead of having a custom read handler that inserted the bit forcefully. Also added a PORT_CUSTOM for the ticket dispenser callback as well. Updated the dcheese driver to use it. Many more drivers can be updated to use these new PORT_CUSTOMs in the future, eliminating hacky input port read handlers. [Aaron Giles]
No.05228 mahlemiut Developer Dec 1, 2009, 21:18	Changes to the input port system in 0.135u2 haven't affected this bug.
No.05330 mahlemiut Developer Dec 28, 2009, 01:51	Attached a potential fix. Seems to work for Zaxxon and Ladybug. Hopefully it doesn't cause any major issues (just seems too easy for something that has been around for the past 10 releases) Have yet to test it in MESS, will do that now.
No.05334 etabeta Developer Dec 28, 2009, 10:25	your patch has been accepted