DOS ain't dead

IRQ ISR IDT [4] Missed the point (DOSX)

posted by Japheth , Germany (South), 17.08.2007, 10:50

> You missed the point

> The target of my criticism "desperately slow and unusable" was "the idea
> of using INT $31 to install a high frequency ISR under DPMI, slow because
> of CPU and DPMI design"

No. You won't gain much by modifying IDT directly. The 180 kHz limit is mainly caused by a slow! write to the video memory inside the ISR. A real-mode version of the test program - where calling the ISR is done without overhead - also stopped at the very same frequency.

---
MS-DOS forever!

Complete thread:

• IRQ ISR IDT - DOS386, 13.08.2007, 07:05 (DOSX)
  • IRQ ISR IDT - Japheth, 13.08.2007, 08:18
    • IRQ ISR IDT [2] - DOS386, 13.08.2007, 08:34
      • IRQ ISR IDT [2] - Japheth, 14.08.2007, 22:24
        • IRQ ISR IDT [3] Very weeeird results - DOS386, 16.08.2007, 10:28
          • IRQ ISR IDT [3] Very weeeird results - Japheth, 16.08.2007, 14:24
            • IRQ ISR IDT [4] Missed the point - DOS386, 17.08.2007, 00:58
              • IRQ ISR IDT [4] Missed the point - Japheth, 17.08.2007, 10:50
                • IRQ ISR IDT [5] RM ISR vs PM ISR - DOS386, 19.08.2007, 07:46
                  • IRQ ISR IDT [5] RM ISR vs PM ISR - Rugxulo, 21.08.2007, 03:16
                    • IRQ ISR IDT [5] RM ISR vs PM ISR - Japheth, 21.08.2007, 08:28
                      • IRQ ISR IDT [5] RM ISR vs PM ISR - Rugxulo, 22.08.2007, 00:13
                        • IRQ ISR IDT [5] RM ISR vs PM ISR - Steve, 23.08.2007, 13:42
                          • IRQ ISR IDT [5] RM ISR vs PM ISR - rr, 23.08.2007, 15:25
                            • IRQ ISR IDT [5] RM ISR vs PM ISR - Steve, 24.08.2007, 01:11