From a0cc6ed5f21438cede5a99535200d91ec1734904 Mon Sep 17 00:00:00 2001 From: "E. C. Masloch" Date: Fri, 19 Jun 2026 22:40:35 +0200 Subject: [PATCH 1/3] change 21.5F07/.5F08 to DOS 4+, note on mistake --- .../INT 215F07 DOS 5 ENABLE DRIVE.txt | 5 ++++- .../INT 215F08 DOS 5 DISABLE DRIVE.txt | 5 ++++- 2 files changed, 8 insertions(+), 2 deletions(-) diff --git a/source/Interrupt List/INT 21 DOS Function Calls/INT 215F07 DOS 5 ENABLE DRIVE.txt b/source/Interrupt List/INT 21 DOS Function Calls/INT 215F07 DOS 5 ENABLE DRIVE.txt index 199f20e0..3ef077d0 100644 --- a/source/Interrupt List/INT 21 DOS Function Calls/INT 215F07 DOS 5 ENABLE DRIVE.txt +++ b/source/Interrupt List/INT 21 DOS Function Calls/INT 215F07 DOS 5 ENABLE DRIVE.txt @@ -5,7 +5,7 @@ Flag: n/a ---------------------------------------------------------------------------- -INT 21 - DOS 5+ - ENABLE DRIVE +INT 21 - DOS 4+ - ENABLE DRIVE AX = 5F07h DL = drive number (0=A:) Return: CF clear if successful @@ -14,5 +14,8 @@ Return: CF clear if successful Notes: simply sets the "valid" bit in the drive's CDS this function is not supported by Novell DOS 7 through at least Update 4, but support was added by Update 13 + previous revisions of this entry claimed it was a "DOS 5+" + function, however the 2024 April release of MS-DOS v4.00 + source texts under the MIT license show it already existed SeeAlso: AH=52h,AX=5F08h"DOS" diff --git a/source/Interrupt List/INT 21 DOS Function Calls/INT 215F08 DOS 5 DISABLE DRIVE.txt b/source/Interrupt List/INT 21 DOS Function Calls/INT 215F08 DOS 5 DISABLE DRIVE.txt index 5b467442..070bdb22 100644 --- a/source/Interrupt List/INT 21 DOS Function Calls/INT 215F08 DOS 5 DISABLE DRIVE.txt +++ b/source/Interrupt List/INT 21 DOS Function Calls/INT 215F08 DOS 5 DISABLE DRIVE.txt @@ -5,7 +5,7 @@ Flag: n/a ---------------------------------------------------------------------------- -INT 21 - DOS 5+ - DISABLE DRIVE +INT 21 - DOS 4+ - DISABLE DRIVE AX = 5F08h DL = drive number (0=A:) Return: CF clear if successful @@ -14,5 +14,8 @@ Return: CF clear if successful Notes: simply clears the "valid" bit in the drive's CDS this function is not supported by Novell DOS 7 through at least Update 4, but support was added by Update 13 + previous revisions of this entry claimed it was a "DOS 5+" + function, however the 2024 April release of MS-DOS v4.00 + source texts under the MIT license show it already existed SeeAlso: AH=52h,AX=5F07h"DOS" From 1a739b5b5437167fb8c184f13a82e15a25927648 Mon Sep 17 00:00:00 2001 From: "E. C. Masloch" Date: Fri, 19 Jun 2026 22:41:51 +0200 Subject: [PATCH 2/3] rename 21.5F07/.5F08 files to indicate DOS 4 --- ...7 DOS 5 ENABLE DRIVE.txt => INT 215F07 DOS 4 ENABLE DRIVE.txt} | 0 ...DOS 5 DISABLE DRIVE.txt => INT 215F08 DOS 4 DISABLE DRIVE.txt} | 0 2 files changed, 0 insertions(+), 0 deletions(-) rename source/Interrupt List/INT 21 DOS Function Calls/{INT 215F07 DOS 5 ENABLE DRIVE.txt => INT 215F07 DOS 4 ENABLE DRIVE.txt} (100%) rename source/Interrupt List/INT 21 DOS Function Calls/{INT 215F08 DOS 5 DISABLE DRIVE.txt => INT 215F08 DOS 4 DISABLE DRIVE.txt} (100%) diff --git a/source/Interrupt List/INT 21 DOS Function Calls/INT 215F07 DOS 5 ENABLE DRIVE.txt b/source/Interrupt List/INT 21 DOS Function Calls/INT 215F07 DOS 4 ENABLE DRIVE.txt similarity index 100% rename from source/Interrupt List/INT 21 DOS Function Calls/INT 215F07 DOS 5 ENABLE DRIVE.txt rename to source/Interrupt List/INT 21 DOS Function Calls/INT 215F07 DOS 4 ENABLE DRIVE.txt diff --git a/source/Interrupt List/INT 21 DOS Function Calls/INT 215F08 DOS 5 DISABLE DRIVE.txt b/source/Interrupt List/INT 21 DOS Function Calls/INT 215F08 DOS 4 DISABLE DRIVE.txt similarity index 100% rename from source/Interrupt List/INT 21 DOS Function Calls/INT 215F08 DOS 5 DISABLE DRIVE.txt rename to source/Interrupt List/INT 21 DOS Function Calls/INT 215F08 DOS 4 DISABLE DRIVE.txt From 359b062f122fe758a2970310b13c03fee570cf24 Mon Sep 17 00:00:00 2001 From: "E. C. Masloch" Date: Fri, 19 Jun 2026 22:50:11 +0200 Subject: [PATCH 3/3] describe 21.5F07/.5F08 conditions in detail --- .../INT 215F07 DOS 4 ENABLE DRIVE.txt | 5 +++++ .../INT 215F08 DOS 4 DISABLE DRIVE.txt | 5 +++++ 2 files changed, 10 insertions(+) diff --git a/source/Interrupt List/INT 21 DOS Function Calls/INT 215F07 DOS 4 ENABLE DRIVE.txt b/source/Interrupt List/INT 21 DOS Function Calls/INT 215F07 DOS 4 ENABLE DRIVE.txt index 3ef077d0..bddc23a4 100644 --- a/source/Interrupt List/INT 21 DOS Function Calls/INT 215F07 DOS 4 ENABLE DRIVE.txt +++ b/source/Interrupt List/INT 21 DOS Function Calls/INT 215F07 DOS 4 ENABLE DRIVE.txt @@ -12,6 +12,11 @@ Return: CF clear if successful CF set on error AX = error code (0Fh) (see #01680 at AH=59h/BX=0000h) Notes: simply sets the "valid" bit in the drive's CDS + in MS-DOS v4.01 and v5.00, the drive is checked to exist in the + CDS array and it is checked that the DPB pointer's low word + is not zero, see offset 45h in #01643. if these conditions + are met, the offset 43h flag mask 4000h ("physical drive") is + set, otherwise error 000Fh is returned. this function is not supported by Novell DOS 7 through at least Update 4, but support was added by Update 13 previous revisions of this entry claimed it was a "DOS 5+" diff --git a/source/Interrupt List/INT 21 DOS Function Calls/INT 215F08 DOS 4 DISABLE DRIVE.txt b/source/Interrupt List/INT 21 DOS Function Calls/INT 215F08 DOS 4 DISABLE DRIVE.txt index 070bdb22..553b2dea 100644 --- a/source/Interrupt List/INT 21 DOS Function Calls/INT 215F08 DOS 4 DISABLE DRIVE.txt +++ b/source/Interrupt List/INT 21 DOS Function Calls/INT 215F08 DOS 4 DISABLE DRIVE.txt @@ -12,6 +12,11 @@ Return: CF clear if successful CF set on error AX = error code (0Fh) (see #01680 at AH=59h/BX=0000h) Notes: simply clears the "valid" bit in the drive's CDS + in MS-DOS v4.01 and v5.00, the drive is checked to exist in the + CDS array and it is checked that the DPB pointer's low word + is not zero, see offset 45h in #01643. if these conditions + are met, the offset 43h flag mask 4000h ("physical drive") is + cleared, otherwise error 000Fh is returned. this function is not supported by Novell DOS 7 through at least Update 4, but support was added by Update 13 previous revisions of this entry claimed it was a "DOS 5+"