Ok, so I figured out the process of making your own 4145B Boot Disk using info from around the web etc, so I thought I'd document it here for posterity and to help anyone else who needs it.
First up you'll need a couple things:
- PC with 3.5" floppy disk drive (This
MUST be directly connected to the motherboard, USB disk drives WILL NOT work due to the low level access required).
- A 3.5" floppy disk, HD is fine, we'll reformat it as needed later.
- A CD and CD/DVD burner.
- The attached CD .iso file.
Unfortunately I don't have an old PC that supports USB boot, so I currently can't make instructions for that, check here for USB boot instructions:
https://torlus.com/floppy/forum/viewtopic.php?p=24043&sid=90a698af4dbda5c4568c26813d8da371#p24043If anyone makes a disk using a bootable USB key, feel free to document the exact process in this thread.
- First up, you'll need to burn the attached disk image to CD. Any software (even late versions of Windows can do it) that can burn a .iso file is fine.
- Boot the PC with the boot CD, you will be greeted with a command prompt at drive A:
- Put some tape over the hole in the top corner of the 3.5" disk (Opposite side to the movable write protect window) to tell the disk drive that the disk is a Double Density (DD) disk instead of a High-Density (HD) disk.
- With the 3.5" disk in the disk drive, type 'FORMAT B: /T:80 /N:9' to correctly format the disk as a DD 720K disk. (Substitute your disk drive letter if needed).
Don't set a Volume label, you can also format as many disks as you need one after the other here.
- Once the disk drive has finished buzzing and groaning and your disk is formatted, type 'R:\IMGDISK\IMD' to select the R: drive to access the Image Disk files on the CD and start the Image Disk software.
- Hit the 'ESC' key to close the intro screen and then press the 'S' key at the main menu page of Image Disk to set the following settings:
- Drive: A (Try other letters if it doesn't work for some reason)
- Cylinders: 83
- Sides: One
- Double-step: Off
- R/W gap: Calculated
- Format gap: Calculated
- Format Fill: E5
- Full analysis: No
- Interleave: Best Guess
- Retries: 5
- Keep bad sector: No
- 500kbps -> 500kbps
- 300kbps -> 300kbps
- 250kbps -> 250kbps
- Press 'ESC' to escape back to the main menu, then press 'W' to select the disk image to write.
- Delete 'A:\' in the file selection field and type 'R:\', then hit 'ENTER'. Hit 'ENTER' on 'IMGDSK\' then press left key and hit 'ENTER' on '4145BDSK' to select the disk image.
- Folow the screen prompts and wait a few minutes until it's finished and then go boot your 4145B!