Controller inputs are ignored for a couple seconds when the HDMI video mode changes

[c0d3h4x0r]

Problem:

The MiSTer process blocks while writing console output to the slow serial port. It cannot handle user input until it finishes writing to the console.

Many games (examples: Sonic the Hedgehog 2 for MegaDrive, or Agony for Amiga) change the core resolution during gameplay. With vscale_mode=4 or vscale_mode=5, that causes an HDMI video mode change. MiSTer remains unresponsive for a noticeable time (~0.5 - 2.0 seconds) after the video mode change while it writes verbose information about the video mode change to the console. The user's controller inputs are ignored during this time, even though the game is still running. This interferes with gameplay.

The duration of unresponsiveness depends upon the size of the user's .ini file, because it gets parsed, processed, and logged twice on every HDMI video mode change.

The impact of the issue varies depending upon the game being played. For games that switch resolutions at the beginning of a new level (such as an action-packed shooter), losing control for a couple seconds at the start is a big problem.

[c0d3h4x0r]

I have posted a workaround for this problem here: https://github.com/MiSTer-devel/Scripts_MiSTer/pull/110

[c0d3h4x0r]

I just realized I probably should have filed this against MiSTer_Main instead. I will re-file it over there and close this one.