Search found 9 matches

by Mills
Sun 02 Sep, 2018 8:43 am
Forum: Development
Topic: VGA Pixel panning registers
Replies: 6
Views: 832

Re: VGA Pixel panning registers

Thanks! :D
by Mills
Wed 29 Aug, 2018 7:45 pm
Forum: Development
Topic: VGA Pixel panning registers
Replies: 6
Views: 832

VGA Pixel panning registers

Hi everybody!. Testing some turbo C programs on PCEM, I discovered everything works great. But I think I found a "bug" in the VGA emulation, so I'll post my tests here. I made a simple program to scroll the screen using VGA hardware registers, based on this: ega-and-vga-smooth-scrolling-and-panning ...
by Mills
Thu 07 Dec, 2017 2:54 pm
Forum: General
Topic: 8086 emulation
Replies: 31
Views: 3849

Re: 8086 emulation

Thanks ruben_balea and SarahWalker, It now runs really well :). I have the "ZIVpackED by Eric ZMIRO 1991" copy, so everything ok. TITUS in CGA mode runs JUST as I remember on my 8086/8 using the Amstrad 3086 config. Maybe it's something to do with the emulation, or maybe the EGA and VGA really speed...
by Mills
Wed 04 Oct, 2017 10:19 am
Forum: General
Topic: 8086 emulation
Replies: 31
Views: 3849

Re: 8086 emulation

Well it's true a lot of abandonware sites make money with that games, and the games are sometimes bad copies that don't work well on original hardware. For example I had a bad lemmings copy, probably from an abandonware site I don't remember now. I had many of these games in floppies back in the day...
by Mills
Tue 03 Oct, 2017 7:16 pm
Forum: General
Topic: 8086 emulation
Replies: 31
Views: 3849

Re: 8086 emulation

Regarding "Titus the Fox": I tested a cracked copy of the game and: - Works fine on a 286 and higher - Crashes (black screen) after executing the COM file on any 8088 and 8086 All the manuals and web pages I read state that the game runs on a IBM PC or XT, so my conclusion is that the might be a bu...
by Mills
Tue 03 Oct, 2017 10:16 am
Forum: General
Topic: 8086 emulation
Replies: 31
Views: 3849

Re: 8086 emulation

I've made some tests with Generic XT clone and IBM XT (both have 8088 CPU) with VGA video adapter and MS-DOS 6.22. Norton Commander -> OK version 4 and therefore all versions up to 4 should work also, version 5 already requires a 286 or higher. Lemmings 1 -> OK, of course at 4.77 MHz takes more tim...
by Mills
Mon 02 Oct, 2017 10:23 pm
Forum: General
Topic: 8086 emulation
Replies: 31
Views: 3849

Re: 8086 emulation

Programs not working in 8088 emulation: -norton commander -lemmings1 -titus the fox When running them, the pc just stays forever in a black screen. I'm sure that it is a native 8088/86 behavior due to the lack of CPU instructions needed by complex programs created much later than a PC XT. Replacing...
by Mills
Sat 30 Sep, 2017 10:38 am
Forum: General
Topic: 8086 emulation
Replies: 31
Views: 3849

Re: 8086 emulation

8086/8088 can only access 1MB or memory, to use HIMEM.SYS you need at least a 286 with enough memory, on some chipsets even with only 1 MB you'll get a small amount of extended memory, Almost any 8086 program should work perfectly on a 8088 because all IBM PC and XT models and most of their clones ...
by Mills
Fri 29 Sep, 2017 6:26 pm
Forum: General
Topic: 8086 emulation
Replies: 31
Views: 3849

8086 emulation

Hi, I'm new in PCem so I might be doing something wrong. I wanted to emulate a machine like this: 8086 8 Mhz 640 kb ram VGA (I really wanted to emulate PS/2 Model 30 8086 with MCGA, But it is OK with the VGA). Some of the predefined machines show a 8086 cpu type, like Amstrad PC1512 for example. But...