DOS ain't dead

USBDDOS USB-for-DOS tester v2.0.0-alpha.1.1 (Announce)

posted by RayeR , CZ, 15.06.2026, 15:06
(edited by RayeR on 17.06.2026, 14:39)

Anybody else tried yet?
Maybe it could work with flashdisk formatted with FS-only, not partition table?
EDIT: no, it parses partition table and correctly read VBR and BPB, I added some debug outputs at init phase and looks OK... but dir command later is bad...

MBR CHS: 2/255/63, partition start CHS: 0/32/33, LBA 2048
VBR HS: 255/63, 4 sectors per cluster, 8 reserved, 2048 hidden, 512 root entries (32 sect.)
root dir start at LBA: 2176
entry #0 - volume label "MR_SD32MB"
entry #1 - LOCALE
entry #2 - COMMAND.COM
...

H:\USBDDOS.SRC\MAKE\OUTPUT>usbddosp.exe /disk                                   
No driver found at port: 5 for device (class 0b/00/00 smartcard), skip     
MSC_ReadSector: dev=291ac, sect=0, cnt=1                                   
partition 0 - LBA start: 2048                                               
FAT partition found (type: 14)                                             
MSC_ReadSector: dev=291ac, sect=2048, cnt=1
Sector per FAT: 60, 60, FATs: 2 - OK
Sector per cluster: 4 - OK
Reserved sectors: 8 - OK
RootDirCluster7.0+: 414e204fh - bad
Label7.0+: ¸àŽÀ‰î‰ï¹ - bad
Label4.0: MR_SD32MB  - OK
Serial7.0+: 7c00bdd8 - bad
Serial4.0: ac8edda8 - OK
VBRSector: 2048 - OK
RootDirs: 512 - OK
USB Disk 'Generic Mass Storage Device' mounted as drive N:.

C:\>dir n:

 Volume in drive N is MR_SD32MB
 Directory of N:\

LOCALE       <DIR>           01-04-14   4:56p
        1 file(s)              0 bytes
                      10,618,880 bytes free



UPDATE:
I enabled serial port debugging and added call of DBG_Log() into BOOL USB_MSC_ReadSector() but I still can see just only 2 read sectors call (MBR and VBR) on terminal log. I cannot explain how it can read part of root dir when there's no such sector read.

---
DOS gives me freedom to unlimited HW access.

Complete thread:

• USBDDOS USB-for-DOS tester v2.0.0-alpha.1.1 - RayeR, 08.06.2026, 16:02 (Announce)
  • USBDDOS USB-for-DOS tester v2.0.0-alpha.1.1 - Japheth, 09.06.2026, 09:47
    • USBDDOS USB-for-DOS tester v2.0.0-alpha.1.1 - RayeR, 09.06.2026, 14:57
      • USBDDOS USB-for-DOS tester v2.0.0-alpha.1.1 - RayeR, 15.06.2026, 15:06