Thanks Ken. I did a write up on the two patches that are needed. * base patch, to clear the hole for the subsequent patches * hardware scroll patch, which overlays
Comments welcome. Document is zipped and is word. On Wed, Feb 23, 2022 at 10:00 AM Ken Pettit <petti...@gmail.com> wrote: > Hey Steve, > > Great job! 72 seconds still isn't bad considering you still have to > update the scroll value on 10 LCD controllers and copy one line from the > bottom controller to the top controller, plus all the added logic to keep > track of which line is which. > > And it is always satisfying to finish a project that was started years > earlier. This was the case with NADSBox ... I released it in 2009 but > actually started in 2002 and then dropped it for several years. > > Ken > > On 2/22/22 10:23 PM, Stephen Adolph wrote: > > So, as a figure of merit, I decided to use A-DUEL.BA as a listing source. > Under these conditions - virtualT @ 2.5MHz > Listing took 72 seconds with hardware scroll "on" > Listing took 120 seconds with no hardware scroll. > The speed up is pretty reasonable, but not like 10x faster or anything. > > (and I found my bug - fixed - and found another, but that can be a > something for the next session) > > Steve > > > On Wed, Feb 23, 2022 at 12:44 AM Stephen Adolph <twospru...@gmail.com> > wrote: > >> Well, I started this little activity in 2006. >> >> I have a pretty good working "hardware scroll patch" now running in >> virtual T! >> >> Recall- >> * the M100 LCD drivers have a hardware scroll mode >> * M100 does not take advantage of it to speed things up. >> * I previously made a patch to the M100 rom that frees up 150 bytes. >> * I've used most of that free space now to implement a patch that uses >> hardware scroll. >> >> The only condition that this patch corrects is the condition when an >> entire 8 lines of screen is being scrolled either up or down. >> >> Other speed ups are imaginable but are much more complex to implement. >> >> I have one last bug that I know of to fix, and when I get that done I >> will share it so others can give it a try! >> >> Steve >> > >
<<attachment: Hardware_scrolling_patch.zip>>