I dont know if you recall this, but I have reported several times that using the custom video mode for the PiTop will cause games with smooth scroll to show hiccups once in a while.
I also have an HDMI screen with the same native resolution as the PiTop screen, 1360x768. The results when using that mode are the same, with the occasional hiccups in framerate.
I reported it to rrossi, the BCM64 creator (BMC64 is THE baremetal C64 emulator for the Pi, no OS involved), because I had the same problem with BMC64, and he fixed it!!!, look: https://github.com/randyrossi/bmc64/blo ... .md#timing
So now, I have this on config.txt:
Code: Select all
# Custom 1360x768 50Hz
hdmi_cvt=1360 768 50 3 0 0 0
hdmi_group=2
hdmi_mode=87
Code: Select all
machine_timing=pal-custom cycles_per_refresh=980670
This is because 1360x768 50Hz is NOT exactly 50Hz, but 49.89Hz, and BMC64 takes this into account, while ADFFS does not.
So, could you please implement a solution for custom "floating point" framerates when a custom mode is used? That would bring perfect refresh rate to ADFFS, like in BMC64.