PCemV17macOS

MacOS port of PCem low-level PC hardware emulator PCem V17. Experimental OpenGL 3 port.

Under macOS 10.14 (Mojave) and 10.15 (Catalina):

Step 1: Install Xcode command-line tools

You need Xcode command-line tools from Apple in order to install Home Brew. You can install Xcode from the App Store or, when you run the Home Brew install script (step 2), it will install the command-line tools for you.

Step 2: Install Home Brew

Home Brew is the package manager for macOS that makes it easy to install the required packages needed for PCem to compile successfully. You can get it from https://brew.sh or run the following command from a Terminal shell:

/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install.sh)"

Step 3: Install the required packages needed by PCem

In order to compile PCem on macOS you'll need sdl2, wxmac and openal-soft packages (Note: Later versions of macOS already have openal-soft so you may not need to install it using Home Brew). You can install theses with the following commands:

brew install sdl2 wxmac openal-soft

Step 4: Download the Source Code

Download the source code from this repository and change directory to the PCem install folder.

Example: cd /PCemV17macOS-master

Step 5: Build PCem

Run the configuration script:

./configure --enable-release-build

If you want networking support:

./configure --enable-networking --enable-release-build

Assuming the command completes successfully run:

make -j4 -Wl,headerpad_max_install_names

This uses 4 threads in parallel and makes space for dylibs to be renamed later (in bundles).

This will take a while. You may see some warning messages during the make process but they do not seem to cause any issues with the compile. Once it completes you'll have the pcem executable file in the install folder. To start the program just run ./pcem from the terminal. You will need to obtain the required ROM files for the machine you want to emulate and need at least one valid ROM for pcem to start. These go in the roms folder located in the folder where PCem is installed.

Under macOS 11 (Big Sur):

1. Follow the same steps 1-4 as described above for Mojave & Catalina, but ommitting the command to install wxmac via Homebrew.

If wxmac is already installed, in Terminal run:

brew uninstall wxmac

Alternatively, you can go to /usr/local/Cellar and move the wxmac folder elsewhere, unless/until you want the unmodified Homebrew version installed again.

2. Download wxmac from source:

https://github.com/wxWidgets/wxWidgets/releases/download/v3.0.5.1/wxWidgets-3.0.5.1.tar.bz2

cd to the wxWidgets-3.0.5.1 folder and run:

./configure --prefix=/usr/local/Cellar/wxmac/3.0.5.1_1 --enable-clipboard --enable-controls --enable-dataviewctrl --enable-display --enable-dnd --enable-graphics_ctx --enable-std_string --enable-svg --enable-unicode --with-expat --with-libjpeg --with-libpng --with-libtiff --with-opengl --with-osx_cocoa --with-zlib --disable-precomp-headers --disable-monolithic --with-macosx-version-min=10.15 --disable-webview

Then run:

make install

This creates the wxmac libraries and the path to the config file is:

/usr/local/Cellar/wxmac/3.0.5.1_1/bin/wx-config

Download the PCemV17 source as above, cd into the folder and run the following configure command:

./configure --enable-networking --enable-release-build --with-wxdir=/usr/local/Cellar/wxmac/3.0.5.1_1/bin/

Then run:

make

This should result in the successfull compilation of the 'pcem' executable. Running it should produce the standard initial error message that no ROMs are present.

Application and usage notes on OSX Mojave

Building and running

No need for brew, can do macports. Just install SDL2 and WxWidgets.

Hardware / device emulation

Dynamic recompilation

Looks like for any CPU above 486 there is the cpu_use_dynarec setting enabled. This, however, just doesn't work. So, whenever the Motherboard/CPU configuration is changed, I manually edit the config file to set the

cpu_use_dynarec = 0

Generally, CPUs above 486 seem to run much slower, likely due to the dynamic recompilation disabled. Also, no overdrive CPUs supported.

Floppy/CD-ROM drive images

It looks like the GUI is incomplete. As such, the image files have to be added by hand, through editing the text config file.

NOTE: Avoid relative paths for volumes - unpredictable results guaranteed (including, but not limited to the volume corruption).

CD-ROM emulation

The CD-ROM emulation appears to be broken. Fixing probably needs importing OSX specific code from SDL.

SCSI settings

For Adaptec:

IRQ: 10
DMA: 7

For Buslogic:

IO: 0x334

No networking

NE2000 is a problem under some OSes (in particular, FreeBSD 2.2.7) as it has resource conflicts.

Also, likely needs pcap driver on host or something else to support the virtual networking.

Some keyboard mappings

IBM PC Key	Maps to
delete	fn-delete
Page Up	fn-arrow up
Page Down	fn-arrow down
Enter	fn-return
Num Pad Enter	fn-return
Backspace	fn-delete
Ctrl-Alt-Delete	⌘ Command

NOTE: after Ctrl-Alt-Delete or a programatic reset, make sure to click on the output window to restart normal operation.

Notes on FreeBSD 2.2.7

A working PCem v17 configuration for a Pentium 120 would be a Socket 7 motherboard (like an Intel VS440FX or Gigabyte GA-686BX) with a 120MHz Pentium CPU, at least 64MB of RAM, a Diamond Stealth 3D 2000 graphics card, and a Sound Blaster 16 audio card. A compatible sound card like the Sound Blaster 16 and a Diamond Stealth 3D 2000 graphics card are good choices for a mid-1990s PC build.