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joncampbell123 / dosbox-x

DOSBox-X fork of the DOSBox project
GNU General Public License v2.0
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Update CGA emulation to support hardware trickery in "8088 MPH" demo #44

Open joncampbell123 opened 9 years ago

joncampbell123 commented 9 years ago

Either directly within DOSBox-X or as a fork, I would like to see cycle accurate emulation of an IBM 5150.

If it can run demos like "8088 MPH" then it's accurate enough.

Probably not going to happen for quite awhile.

At the time of entering this, the demo not only complains about CPU speed but also some parts drive the CGA video emulation crazy!

The reason I suggest a fork is that the changes to accomplish this might be substantial enough that modifying the code to do it might break the code. It might be better to have a fork where all but 8088+CGA/MDA emulation is removed and everything is modified to emulate the IBM 5150 as closely as possible.

joncampbell123 commented 9 years ago

Asking for cycle-accurate emulation is silly. Let's just update the CGA emulation to support the demo's weird tricks.

http://8088mph.blogspot.com/2015/04/cga-in-1024-colors-new-mode-illustrated.html

Torinde commented 1 year ago

Two other emulators who focused on executing 8088MPH properly:

dbalsom/martypc

Emulation of the 8237A DMA controller and the CGA board (with its 6845 CRTC) has been made cycle-exact as well

PCbox says it can

Run certain demos that don’t work on much else than real hardware (Like 8088MPH, for instance)