I've posted patch file only. If you need BIOS ROM image file for testing, please send PM for me.

Edit : This patch has been incorporated here.

This patch adds machines using Chips&Technologies SCAT chipset. 1. GW-286CT GEAR Uses Chips&Technologies BIOS. The BIOS is available [Moderator : Please don't post links to copyrighted material]. GW286CT-1.png 2. Samsung SPC-4216P Successor of Samsung SPC-4200P. The BIOS is attached this pos...

I also received "Sorry, the board attachment quota has been reached." message today when adding attachment files on post.

Hello. Many thanks. It Works!! I tested Windows 3.0 in real mode (win /r), with QRAM and a mouse driver loaded high. I saw this with the manifest utility. So there was only a conflict between the Qram driver and the EMS driver. Sorry if I'm asking too much Is possible to add 1MB support of EMS RAM ...

Hello. Thanks for the reply. I don't know where put the EXCLUDE line after QRAM is installed. It is how the CONFIG.SYS looks like. Device=C:\qram\qext.sys (QRAM custom XMS driver) device=C:\qram\qram.sys R:1 device=C:\qram\loadhi.sys /R:1 EMM.SYS FRAME=E000 (I changed it because QRAM puts C000 by d...

Hello. I recently tested the EMS memory emulation. The only issue i found is when the a UMB driver is loaded, or when the EMS driver is loaded in UMB itself. The drivers install sucecifully in UMB memory (like the mouse) but the OEMSTEST.EXE from Douglas Boling. (he developed varios EMS 4.0 test in...

This patch implements to automatically switch memory addressing emulation between 256KB*8 and 1MB*2 configuration when using 2MB memory. Samsung SPC-4200P now properly works again when using 2MB memory.

Edit : This patch has been incorporated here.

This patch does the following.
- Fixed problem where shadow RAM isn't enabled properly when mixed memory configuration is used.
- Improved memory address clipping and mapping emulation accuracy.

This patch improves memory address clipping and mapping accuracy.

Edit : This patch has been incorporated here.

Lots of improvements for the 286 Greatpsycho! Is that your favorite processor? I have a 286 PC purchsed in 1992 and it is still operatable. So I'm working on it. Emulation of Award286 clone is working properly at most common cases, but it is still imperfect and there are lot of things to implement.

This patch improves memory configuration setting accuracy when 1MB memory installed.

Please set extended memory size to 0 if 1024KB memory used to avoid CMOS memory size error. AMI286 in PCem uses Chips & Technologies NEAT chipset, but its emulation is still poor. NEAT chipset supports selecting upper 384KB memory area as shadow memory and extended memory via chipset-specific re...

This patch applies non-string instruction followed by REP instruction to be processed as real machine does. REP prefix should not occur exception #6 even if non-string instruction is followed.

This patch implements NMI mask bit on RTC(Port 0x70).

And this patch also applies to the following.
- Moved initializing a20_mem_key and a20_mem_alt value to mem.c
- Changed initial a20_mem_key and mem_a20_state value to 2

This additional patch the following.

- Moved initializing a20_mem_key and a20_mem_alt value to mem.c
- Changed initial a20_mem_key and mem_a20_state value to 2

Edit : This patch has been incorporated here.

SA1988 wrote:The latest commit (in x86seg.c where it says "x86ss("Load CS call not present", seg & 0xfffc);" ) breaks win3.0 in protected mode. It should be set to x86np.

It seems 86Box's trouble. PCem doesn't have this problem.

Just confirming that this is a regression compared to PCem v10.1 on the same system, where A20 seems to be handled correctly. EDIT: Okay, this is getting weird. I was finally able to get HIMEM.sys working on PCem v11, but only on a certain BIOS in a certain very specific setup. Specifically, if I u...

This patch applies add Samsung SPC-4200P machine. Reworked against rev 794.

Edit : Fixed wrong SPC-4200P nvr file name in nvr.c

This patch does the following

- LTR instruction set TSS state to busy.
- LMSW instruction does not alter ET bit in CR0 register.
- Improved accuracy destination IP address calculation in protected mode JMP and CALL instruction via system segment.

More task switching fixes. It fixes OS/2 Warp 4.0 installer crashing.

This patch applies global EMS state and EMS I/O port setting more accurately.

This patch applies improved guessing parameter values low capacity hard disk images that has 17 sectors per track.

This patch improves task switching accuracy. Borland C++ 2.0 for 286(BCX.EXE & BCCX.EXE) and Turbo debugger for 286 no longer crashes.

Speaking of the Commodore PC 30 III, when I select 1,024 KB RAM, the BIOS reports only 640 KB of memory usable. If I select 1,408 KB RAM, the BIOS will report 384 KB of extended memory usable. And at least 1,408 KB of RAM is needed to run Windows 3.0 in Standard Mode. If 1,024 KB RAM is selected, W...

This patch applies experimental 286 TSS switching. Microport UNIX System V-AT 2.3 installer no longer crashes.

This patch breaks the Pentium machines. For example, Intel Advanced/EV now hangs at POST. I really don't think all AT-class machines with IDE should have the top 384 kB remapped. You're right. Remapping top 384k memory should be applied only no shadowram support machine like IBM AT or AT compatible...

OKay! :D Most 386SX and 386DX-based motherboards had as little as 512 KB of base RAM. I believe that the Commodore PC 30 III was released in 1988 and it was configured with either 512 KB or 640 KB of RAM: http://www.homecomputer.de/pages/MachineInfo/Commodore_PC-30_III.html I also believe that the ...

Awesome! I'm wondering if it's possible to apply this patch to AMI 386SX/386DX clone as well as the Commodore PC 30 III and Dell System 200 machines as well! :) It's easy job. Please let me know what machines have less than 1MB memory when it ls released. OKay! :D Most 386SX and 386DX-based motherb...

Great work on the memory settings patch! Can this setting be applied to 286, 386 and 386SX clones? I know for a fact that the IBM PS/1 Model 2011 started out with 512 KB of base memory. Yes. I've just added if AT machines granularity value less than 128, consider memory size is MB and greater or eq...

Great work on the memory settings patch! Can this setting be applied to 286, 386 and 386SX clones? I know for a fact that the IBM PS/1 Model 2011 started out with 512 KB of base memory. Yes. I've just added if AT machines granularity value less than 128, consider memory size is MB and greater or eq...