takamichih

1.2M (1M) floppy format
1.232KiB
1024 (bytes/sector) * 1232 (sectors)

mformat command:
mformat -t77 -h2 -s8 -S3 -c1 -m0xfe -r6
  -S3: sector size= 1 << (sizecode+7) = 1024
  -c1: sectors per cluster= 1
  -m0xfe: media descriptor
  -r6: root sectors (192 entries)

takamichih

;; prints message to screen on PC-9800 series text VRAM
;; to create bootable floppy:
;;  1. save this as pyon.asm with shift_jis (CP932) encoding
;;  2. nasm -o pyon.bin pyon.asm
;;  3. (for traditional 1.2MB floppy) cat pyon.bin /dev/zero | dd of=pyon.1232 bs=1k count=1232
;;     (for 1.44MB floppy) cat pyon.bin /dev/zero | dd of=pyon.144 bs=512 count=2880
;;     (of course you might want to write directly to your floppy device instead of the image file if
;;      you happen to own an actual PC-98 to test on)
;;