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  • Testing all video mode - but which ones are graphics ?

    From R.Wieser@21:1/5 to All on Tue Feb 13 08:57:32 2024
    Hello all,

    I've got a small program going thru all video-modi by looping AL from 80
    upto FF, calling INT 10, AH=00.

    I would like to find out which of those modi are graphical. Ralf Browns
    memory list shows 0040:0065 to hold some bits regarding the current video
    mode. In my case the lower two bits are of interrest

    Mode 03, text, shows the value 01. Alas, mode 0D, graphics, also shows 01.
    In fact, only modi 4 thru 6 show a 02 there, and modi 0 and 01 show a 00.
    Al others show 01.

    And I'm pretty sure there are few other graphics modi above mode 06 ...

    tl;dr:
    How do I find out if a certain mode is graphics ?

    Secondary question : if the lower two bits of 0040:0065 are *not* the
    current video-modes graphics and textmode capablities, what do they signify instead ?

    Regards,
    Rudy Wieser

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    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From JJ@21:1/5 to R.Wieser on Tue Feb 13 18:14:38 2024
    On Tue, 13 Feb 2024 08:57:32 +0100, R.Wieser wrote:
    Hello all,

    I've got a small program going thru all video-modi by looping AL from 80
    upto FF, calling INT 10, AH=00.

    I would like to find out which of those modi are graphical. Ralf Browns memory list shows 0040:0065 to hold some bits regarding the current video mode. In my case the lower two bits are of interrest

    Mode 03, text, shows the value 01. Alas, mode 0D, graphics, also shows 01. In fact, only modi 4 thru 6 show a 02 there, and modi 0 and 01 show a 00.
    Al others show 01.

    And I'm pretty sure there are few other graphics modi above mode 06 ...

    tl;dr:
    How do I find out if a certain mode is graphics ?

    Easy way: Use BIOS service to read a pixel. It's only applicable in graphic video mode.

    Hard way: Use the video ports to check the current type of video mode. i.e. graphic or text.

    Secondary question : if the lower two bits of 0040:0065 are *not* the
    current video-modes graphics and textmode capablities, what do they signify instead ?

    See Ralf Brown's Interrupt List.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From R.Wieser@21:1/5 to It also on Tue Feb 13 13:45:46 2024
    JJ,

    How do I find out if a certain mode is graphics ?

    Easy way: Use BIOS service to read a pixel.
    *It's only applicable in graphic video mode.*

    (bolding mine)

    Indeed. And, AFAICT, that means that *you should not be trying to use it*
    in a non-graphics mode.

    It also says squat about what happens if you do try. Which makes it
    useless.

    Hard way: Use the video ports to check the current type of video
    mode. i.e. graphic or text.

    And you don't think that suggestion is a bit ... vague ?

    Secondary question : if the lower two bits of 0040:0065 are *not* the
    current video-modes graphics and textmode capablities, what do they
    signify
    instead ?

    See Ralf Brown's Interrupt List.

    You're a funny guy. Not.

    Whats the matter ? Did you step outof bed with the wrong foot first ? :-(

    Regards,
    Rudy Wieser

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From JJ@21:1/5 to R.Wieser on Wed Feb 14 06:26:49 2024
    On Tue, 13 Feb 2024 13:45:46 +0100, R.Wieser wrote:
    JJ,

    How do I find out if a certain mode is graphics ?

    Easy way: Use BIOS service to read a pixel.
    *It's only applicable in graphic video mode.*

    (bolding mine)

    Indeed. And, AFAICT, that means that *you should not be trying to use it*
    in a non-graphics mode.

    It also says squat about what happens if you do try. Which makes it
    useless.

    Hard way: Use the video ports to check the current type of video
    mode. i.e. graphic or text.

    And you don't think that suggestion is a bit ... vague ?

    Secondary question : if the lower two bits of 0040:0065 are *not* the
    current video-modes graphics and textmode capablities, what do they
    signify
    instead ?

    See Ralf Brown's Interrupt List.

    You're a funny guy. Not.

    Whats the matter ? Did you step outof bed with the wrong foot first ? :-(

    Can't give fish all the time. You gotta fish yourself eventually.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From R.Wieser@21:1/5 to All on Wed Feb 14 07:50:57 2024
    JJ,

    Can't give fish all the time. You gotta fish yourself eventually.

    You know me better than that.

    Besides, how do you think I found that 0040:0065 reference ?

    But tell me, how come you're assuming that I didn't fish for myself ?

    And by the way, nice ignoring me on calling you out on your 'peek a pixel' suggestion.


    Something odd is going on here, and I'm not at all sure anymore that you
    really are JJ.

    Regards,
    Rudy Wieser

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From wolfgang kern@21:1/5 to R.Wieser on Thu Feb 15 09:14:35 2024
    On 13/02/2024 08:57, R.Wieser wrote:

    I've got a small program going thru all video-modi by looping AL from 80
    upto FF, calling INT 10, AH=00.

    ask again in ALA

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From R.Wieser@21:1/5 to All on Thu Feb 15 11:48:06 2024
    Wolfgang,

    I've got a small program going thru all video-modi by looping AL from 80
    upto FF, calling INT 10, AH=00.

    ask again in ALA

    alt.lang.ass I presume ? Really ? Half of it seems to be spam. But hey, I've got little to lose.

    Regards,
    Rudy Wieser

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)