DOS ain't dead

SATA - PATA, "native" - "legacy" (Announce)

posted by tom , Germany (West), 03.12.2007, 18:44

> > But to be sure, how can I detect if INT13h services use DMA?

if the speed is > 8MB/sec, it's using UDMA

most S-ATA BIOS's seem to use UDMA, but - according to Jack, some BIOS
disable UDMA in protected mode, so a protected mode aware driver is
a good idea for S-ATA, too.

> - in v86-mode, the BIOS has to do VDS calls (int 4Bh) if it uses DMA,
> which can be trapped easily.

not necessarily. They could reserve the top memory 64K for that; before
reporting the memory via int 15/E8xx. locking wouldn't be needed for that
memory (or does that not work since EMM386 has to set up pagetables for this region, too?)


Tom

Complete thread:

• Jemm v5.68 - Japheth, 03.12.2007, 09:09 (Announce)
  • Jemm v5.68 - RayeR, 03.12.2007, 11:51
    • SATA - PATA, "native" - "legacy" - Japheth, 03.12.2007, 13:00
      • SATA - PATA, "native" - "legacy" - RayeR, 03.12.2007, 13:22
        • SATA - PATA, "native" - "legacy" - rr, 03.12.2007, 13:57
          • SATA - PATA, "native" - "legacy" - RayeR, 03.12.2007, 15:12
            • SATA - PATA, "native" - "legacy" - Japheth, 03.12.2007, 15:45
              • SATA - PATA, "native" - "legacy" - tom, 03.12.2007, 18:44
                • SATA - PATA, "native" - "legacy" - Japheth, 03.12.2007, 18:57
        • SATA - PATA, "native" - "legacy" - Rugxulo, 04.12.2007, 09:43
        • SATA - PATA, "native" - "legacy" - RayeR, 05.12.2007, 03:29
          • SATA - PATA, "native" - "legacy" - Japheth, 05.12.2007, 09:27
            • SATA - PATA, "native" - "legacy" - RayeR, 05.12.2007, 20:59
              • SATA - PATA, "native" - "legacy" - Laaca, 05.12.2007, 22:16
              • SATA - PATA, "native" - "legacy" - Japheth, 05.12.2007, 23:04
                • SATA - PATA, "native" - "legacy" - RayeR, 06.12.2007, 03:51
                  • SATA - PATA, "native" - "legacy" - Japheth, 06.12.2007, 07:35
                    • SATA - PATA, "native" - "legacy" - RayeR, 06.12.2007, 12:36
                      • SATA - PATA, "native" - "legacy" - rr, 06.12.2007, 17:42
                        • SATA - PATA, "native" - "legacy" - RayeR, 06.12.2007, 17:55
                          • SATA - PATA, "native" - "legacy" - rr, 07.12.2007, 09:48
                            • SATA - PATA, "native" - "legacy" - RayeR, 07.12.2007, 10:46
                          • SATA - PATA, "native" - "legacy" - Rob, 07.12.2007, 11:33
                            • SATA - PATA, "native" - "legacy" - Japheth, 07.12.2007, 12:15
                              • SATA - PATA, "native" - "legacy" - rr, 07.12.2007, 12:35
                              • SATA - PATA, "native" - "legacy" - Rob, 07.12.2007, 14:05
                                • SATA - PATA, "native" - "legacy" - tom, 07.12.2007, 14:58
                                  • SATA - PATA, "native" - "legacy" - rr, 07.12.2007, 15:10
                                    • SATA - PATA, "native" - "legacy" - tom, 07.12.2007, 15:20
                                  • SATA - PATA, "native" - "legacy" - RayeR, 07.12.2007, 22:22
                                • SATA - PATA, "native" - "legacy" - Japheth, 07.12.2007, 15:00
                                  • SATA - PATA, "native" - "legacy" - Rob, 07.12.2007, 17:48
                            • SATA - PATA, "native" - "legacy" - rr, 07.12.2007, 12:38
            • SATA - PATA, "native" - "legacy" - RayeR, 18.12.2007, 02:03