I recently installed an XT bridge board in my Amiga 2000, the A2088XT. I wanted a hard-file for it that was all set up. I am rusty with MS-DOS and I am not motivated to reacquaint myself with it, I have Amiga DOS š
I have wanted a bridgeboard ever since I sold my A1000 sidecar. Here is rough video of me starting the sidecar, you can hear how excited I am. I also have a video on Youtube of the setup described here.
Hard-files, the cheapest virtual HDD
A hardfile is a, usually large, file that behaves for some software or another on the system as if it were a separate hard disk drive. Access is therefore through the host system which has speed implications for the software with the pretend hard drive. They are easy though and work well.
The bridgeboard hard-file format is compatible with the PC-Task format. I actually tested this early in my experiments in getting a hard-file working. I never planned to run a 5.25 inch floppy drive and figured that was OK, the PC Task users don’t either. I do believe I can plug an Amiga floppy into the back of the bridgeboard though.
My concerns began when I realised that a downloadable hard-file for PC Task / Bridgeboard users was not a thing (nor for the incompatible PCX). I did find one, and it worked . It is from the AIBB FTP server. It is just MS-DOS though. It did not like the XT and, once the boot floppy drive fails on startup (I don’t have a drive at all), and after pressing F1 to continue, holding down <Shift> skipped autoexec.bat to leave me with a C prompt. Win.
Making an Amiga PC hard-file from a generic .img
But what about some games? Over on the internet archive I found some cool MS-DOS hard drive images.
I downloaded tdl hdd.img It contains hundreds of megabytes of games organised by year along with terminal software, Total DOS Loader to index and launch games, and other tools. It is a hard drive image designed for a MiSTer. I may buy a MiSTer one day.
This image is not a bridgeboard / PC Task compatible file. However, late last year user “MOS6510” published python code on github to convert raw images to Amiga PC hardfile images. What a legend.
I had never run python before. I downloaded it from the MS Store, opened a command prompt at the location of tdlhdd.img (which I had renamed to remove the space for convenience). Next I typed python and, at the python prompt, followed the github instructions. A new image file was rapidly produced.
Adding a hard-file to a bridgeboard
Once the image was over on the Amiga there was work to do. I had already installed the Janus Tools DOSServ hard drive handling files update from Aminet using the included readme instructions. I am not sure if it is necessary but given the original Janus tools floppy installer only allows for up to 32megabyte hard drives I think it probably is. One future project would be, using the extra DOSServe features, to copy the contents of the hard-file into a HDD partition for better speed too.
I then edited (ed) DH0:PC/System/aboot.ctrl to refer to the new hard drive file. Some notes:
- ‘DH0:PC’ is just where I chose to install the Janus software to from floppy
- I could not simply replace the original hard-file, created on DH0: during installation of the Janus software, my Workbench partition is not big enough
- I had renamed the hard-file to TDL with no extension, the original hard-file created by the Janus setup floppy had no extension (.xxx I mean)
- Following the guide in the Janus Tools package, the aboot.ctrl file has no carriage return
Nothing happened when I reset the XT so I power cycled the Amiga to get Janus to look for a new aboot.ctrl. It booted the Hardfile!
We are in MS-DOS now!
A lack of memory (or memory management ability) caused a minor error (press f for fail after resizing the window a bit) and the computer loaded into Norton commander.
I navigated to c:\Games\1981 and pressed enter to start TDL.exe, chose Eliza 3.0 and started the game using the .bat file that was automatically unpacked to a temporary folder by Total DOS Loader.
Done. Plus, if you review the Eliza screenshot there is a peek into my psyche.
Probably need to buy a ram expansion. Also, no double entendre was intended in the drafting of this post.
Benjamin's Bench 