WD37C65 FDC by Scott M. Baker
Actually Spencer Owen has created with his RC2014 family all the modules you could wish for, but ... A floppy disk controller is definitely missing. Retro computers without a floppy drive are not retro computers! But I could remember that Scott M. Baker wrote a lot of articles about the RC2014. And lo and behold, he also designed two different controllers and even set them as a project directly at Osh Park. What more do you want?
The ordering process at Osh Park was very simple, then ordering the required individual components from Mouser and that was it. The soldering together took just 30 - 40 minutes. Only the controller chip wasn't easy to find. I was lucky that eBay offered several at just the right time at a good price.
Note: I currently order all my PCBs from JLCPCB. The price there is simply unbeatable.
Effort and costs
- PCBs (OSH Park): 9 EUR
- Material (Mouser): 16 EUR
- WDC37C65 (eBay): 7 EUR
- Soldering: 1 hour
How to Prepare an 8" Floppy Disk (C:) with RomWBW
... formatting ...
For this purpose use FDU.COM, change the settings to 8" drive, and then format.
The 8 inch floppy format is as follows: 77 tracks, 2 sides, 15 sectors per track and 512 bytes per sector. The drive rotates with 360 rpm like a 5.25" HD drive. This is not a true 8" format, but simply the 5.25" 1.2MB HD format but only with 77 tracks! But I don't want to complain.
The various floppy formats are actually just the transfer of the known DOS parameters to CP/M. Furthermore RomWBW uses only MFM and not FM, i.e. it always works with 512 bytes per sector.
... clear/prepare the directory ...
clrdir c:
Confirm with capital „Y“ NOT „y“. Took me a while to figure it out!
Note: CLRDIR is not actually necessary for floppy disks, as this is done automatically in the process of formatting!
... make the floppy bootable ...
syscopy c:=cpm.sys (or zsys.sys)
Do NOT use SYSGEN like you are used to on real CP/M machines. Wayne Warten told me: "SYSGEN is kind of brain dead."
... work with the floppy ...
Do whatever you want: PIP, boot, ...
External links
- Dr. Scott M. Baker:
- RC2014 Floppy Controller Boards / Z80 Retrocomputing Part 14
- Qume 842 8″ floppy drive with a RC2014 Z80 retrocomputer
- RC2014 Floppy Controller Boards / Order directly from OSH Park
- Wayne Warthen:
- github.com / RomWBW
- github.com / ROM releases
Internal links
- RC2014 menu