B.L.T. #2: (Howto) Multi-boot DOS on your PC/XT with BTTR BOOTMGR

Welcome to Boring Lecture Time #2, in which I laboriously walk through the process of setting up a dual boot setup with Novell/Digital Research DR-DOS 6 and IBM PC-DOS 7 using BTTR Software's BOOTMGR - multi-BOOT ManaGeR: https://www.bttr-software.de/products... Brought to you in limited edition Retro Deluxe Old-Tymey Comp-O-Vision. (Professor Pterosaur's been at the absinthe again.) I threw this video together because I found this software pretty neat; most modern boot managers require protected-mode capable CPUs, while this fits entirely inside the MBR and works on any XT or higher PC with an INT13 BIOS compatible hard drive controller. (Including the now ubiquitous XTIDE and XT-CF-Lite eight-bit controllers.) The documentation is a little opaque, so maybe at least one person might this detailed walkthrough helpful. If you want to install DOS 3.x and 5-or-later on a disk the procedure is pretty much the same as documented here; partition the disk with the older DOS first and install it, install bootmgr, set the floppy boot entry to hide the 3.x primary partition, and proceed just as shown. DOS 3.3 will understand a large extended partition even though the individual drives inside of it need to be less than 32MB, so I'd suggest cutting that into D: and E: drives, with the D: under 32 MB, so you can use it to shuffle data between the two OSes. And yes, the video quality is laughably bad. As I explain near the end of the video, I went to some lengths so set up the DSLR camera to record the CRT with as little glare as possible and only had the composite capture device running for laughs/in case direct dubs of the PC beeps might be useful. (Likewise I got a dub of the audio on a headset recorder in case the camera mike decided to concentrate on the sound of my breathing again.) Then my memory card filled up about ten minutes into filming and I didn't notice for several more minutes that it had stopped. So, yeah, here we are. I slapped the mono effect on it because as ridiculous as it is it's actually less distracting than the sea of colored dots you get from an 80 column text CGA capture. Demo machine was the Tandy 1000 SUX with a homebrew XT-CF-Lite.