Update
Retronew is a modern equivalent using Allegro.
retrogardens
16bit retro programming in DosBox with Borland C++ 3.1 Turbo Pascal 7 and TASM
Introduction
Prerequisites
DosBox, Borland C++ 3.1 and Turbo Pascal 7.0.
You don't need both BCPP3.1 and TP7, so if you don't want to use Pascal, don't download and install TP7, or vice versa.
I installed TASM 5.5 also, although I am not sure if you really need to do that.
However, below instructions assume that the Turbo Assember is installed into C:\TASM
Also, besure to check out Fabien Sanglard's excellent article Let's Compile Like Its 1992 about how to use DosBox and Borland C++ 3.1 to compile Id Software's Wolfenstein 3D, if you want a walkthrough with lots of picures and well written text.
Where to get it
BC3.1 and TP7
If you don't already have BC3.1, TASM and TP7 lying around, then you can grab them from WinWorld - go to the Library section.
DosBox
Download it from DosBox.com
Dosbox
While you can read (and you probably should) the DosBox setup and installation wiki page , here is a list of things that I did to get up and running.
Firstly, I simply installed DosBox.
C drive
First, we need a place for our development tools to be installed.
In other words, we need a C:\ drive.
I simply created a directory creatively entitled DosBox in my home directory.
General configuration
You shouldn't really have to change anything, other than outlined below.
The configuration file for DosBox is ~/.dosbox/dosbox-0.74.conf on Linux.
Look it up if you are on other platforms.
Autoexec.bat
Open up the dosbox configuration file and navigate to the end, where you will find the autoexec section.
[autoexec]
# Lines in this section will be run at startup.
# You can put your MOUNT lines here.
mount c ~/DosBox
path borlandc/bin;tasm/bin;tp7/tp/bin
c:
We mount the C drive, set up the path and change to the C drive.
Floppy disks
Since we are going to program like it's 1995, we need to deal with floppy disks.
So, since our machine does not have a floppy disk station, we use floppy disk images.
And a directory that we mount as floppy in DosBox.
So, create a directory for the floppy drive, and add a line in the autoexec section of the DosBox configuration file, like so:
mount a -t floppy ~/DOS/box_disks/floppy
Now, what's in the floppy disk directory will be available from the A drive inside of DosBox.
Insert and Change floppy disks
Simply open a floppy image ( disk01.img ) in a disk image viewer, select all files and copy them to the floppy directory.
When the installation program asks for the next disk, simply delete the files in floppy and copy the files of the next disk into it.
Very low tech. But it works! :p
CD ROMs
If you need to mount a CD drive, and you have an iso that you want to mount, then you can do that, like so:
imgmount d ~/DOS/WatcomCPP10.6/watcom10.6.iso -t iso
When you are done with it, simply remove the line, or comment it out (in case you want to mount another iso later).
I have no idea how to swap CDs - but this is DOS and 1995 and I don't recall ever having to swap CDs when installing. :)
Cpu cycles
A CPU speed of 50% works well.
Press Ctrl+F10 to grab the input, and press CTRL+F11 to decrease CPU cycles.
Click CTRL+F10 to release the mouse again.
See the DosBox - Special Keys wiki page for a list of key combos that you can use with it.
DosBox Window
If you want the DosBox to be larger, you can set the size in the [sdl] section.
My settings are:
windowresolution=1024x768
output=opengl
You can also set autolock for the mouse to be off:
autolock=true
Then the mouse will not be grabbed automatically by the DosBox window.
You can use Ctrl+F10 to grab / ungrab it.
DosBox Oddities
If you move files around on your C directory from outside of DosBox, you need to restart it to make DOS see it.
Borland C++ 3.1
General advise
It is a good idea to minimize the use of the mouse when using the Borland C++ IDE.
Don't click with your mouse in the DosBox window, if you don't want DosBox to grab it. Or turn off autolock (see above).
Use the ALT key to quickly issue commands - for example use ALT+P ENTER to open a project, and ALT+R Enter to run your project.
Achtung! Do not use CTRL+F9 to run your project, because that is the DosBox terminate key combo.
Use ALT+[number] to quickly switch between windows.
Project settings
When a project is open, enter the Options menu - ALT+O - and make sure that the following is set:
Application
Dos Standard
Code Generation
Model : Large
Advanced Code Generation
Floating Point : 80287/387
Instruction Set : 80386
Entry/Exit Code Generation
Prolog/Epilog Code Generation : Dos standard
C++ Options
Use C++ Compiler : C++ always
Linker
Output : Standard DOS EXE
Debugger Program Heap Size : 350 K bytes
Directories
Modify the Include / Library directories as needed.
Consider adding C:\GARD\BC31\[project_dir] to the Source Directories.
My Include Directories is:
C:\BORLANDC\INCLUDE;C:\GARD\BC31\COMMON
My Library Directories is:
C:\BORLANDC\LIB;C:\GARD\BC31\COMMON
Make sure that you save the settings before exiting: ALT+O S K
ASM and Turbo Assember
Link shenanigans
In the COMMON directory, there are a couple of files in assembly code that needs to be built.
You can either do this, by first removing the object files from the projejct ( del ), and add the .ASM files ( Ins button in the Project window ) and build them ( ALT+C L ) and then remove them from the project again, and add the object ( .OBJ ) files again.
Or you can simply use Turbo Assembler on the command line.
Don't ask me how to do that :p
TASM.EXE
If Borland complains that it can't find TASM.EXE, then go into Options - Transfer and find ~Turbo Assember and Edit it.
Enter C:\TASM\BIN\TASM.EXE in Program Path and then hit the Modify button.
TASM2MSG.EXE
If Borland complains that it can't find TASM2MSG.EXE, find it in C:\BORLANDC\BIN and place a copy in C:\BORLANDC and a copy next to the .ASM file that you want to link.
Turbo Pascal 7.0
Because TP7 needs to be patched to run with faster CPUs, it is a good idea to use version 7.0, and not 7.1.
Divide by Zero CRT runtime bug
Turbo Pascal works, but will produce executables that crashes with a divide by zero error at runtime.
It will do that on faster CPUs, unless we patch it.
Download the Crt patch for TP7 - get the compile time patches - and extract.
I used the first patch, and checked my TP7 version to figure out which patch to apply (it was the first one).
Copy the files to the bin directory and run PATCH PATCH700 (or PATCH701, depending on the date of your TP7).
Credits
- General ideas and code from Christopher Lampton's book Gardens of Imagination (1994 - Waite Group) Also available from the Internet Archive
- VGA code from David Brackeen's 256-Color VGA Programming in C tutorial.
- Keyboard code from Al Stevens' Raycaster article - Dr. Dobb's Journal
Some code from the dos/programming section of the x2ftp.oulu.fi mirror