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Register Watcher Window. PB/WIN 8.04

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Olav

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Feb 28, 2010, 6:35:28 AM2/28/10
to
Hello,

Can someone please explain what those two lines below mean? I know they is
ment to show the value of the CPU's various status flags; like overflow and
carry flag, but I have never seen these flag values been listed in this way
before - in any software.

FLG 000000001001000110
Flags NC,P,Z,NS,UP,NO,NIO

And what does GS stands for?
--


Wolfgang Enzinger

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Feb 28, 2010, 1:05:35 PM2/28/10
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Am Sun, 28 Feb 2010 12:35:28 +0100 schrieb Olav:

> Can someone please explain what those two lines below mean? I know they is
> ment to show the value of the CPU's various status flags; like overflow and
> carry flag, but I have never seen these flag values been listed in this way
> before - in any software.
>
> FLG 000000001001000110
> Flags NC,P,Z,NS,UP,NO,NIO

Due to the lack of documentation all I can offer are *guesses*. I'm pretty
sure of these:

C = carry flag (bit 0; NC if not set)
P = parity flag (bit 2; NP if not set)
Z = zero flag (bit 6; NZ if not set)
S = sign flag (bit 7; NS if not set)

Not sure about these:

UP = ???
NO = presumably overflow flag (bit 11)
NIO = probably IOPL flag (I/O privileg level, bit 13)

> And what does GS stands for?

That's just one of the six 16 bit segment registers (CS, DS, ES, FS, GS,
SS).

HTH,
Wolfgang

Olav

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Feb 28, 2010, 1:52:55 PM2/28/10
to
Hello again,

Thanks for your response.

"Wolfgang Enzinger" <usene...@temporaryforwarding.com> skrev i melding
news:79pdh4bajlp6.173ix4nc68fym$.dlg@40tude.net...


> Am Sun, 28 Feb 2010 12:35:28 +0100 schrieb Olav:
>
>> Can someone please explain what those two lines below mean? I know they
>> is
>> ment to show the value of the CPU's various status flags; like overflow
>> and
>> carry flag, but I have never seen these flag values been listed in this
>> way
>> before - in any software.
>>
>> FLG 000000001001000110
>> Flags NC,P,Z,NS,UP,NO,NIO
>
> Due to the lack of documentation all I can offer are *guesses*. I'm pretty
> sure of these:
>
> C = carry flag (bit 0; NC if not set)
> P = parity flag (bit 2; NP if not set)
> Z = zero flag (bit 6; NZ if not set)
> S = sign flag (bit 7; NS if not set)

My guesses is the same, but the problem for me is how to read the value.of
the vaarious flags.

John H. Guillory

unread,
Mar 14, 2011, 12:46:20 AM3/14/11
to
On Sun, 28 Feb 2010 19:52:55 +0100, "Olav" <bla..ah@assdasd.nn> wrote:

I know this is old, but perhaps it'll help someone in the future....

>>> FLG 000000001001000110
>>> Flags NC,P,Z,NS,UP,NO,NIO
>>
>> Due to the lack of documentation all I can offer are *guesses*. I'm pretty
>> sure of these:
>>
>> C = carry flag (bit 0; NC if not set)
>> P = parity flag (bit 2; NP if not set)
>> Z = zero flag (bit 6; NZ if not set)
>> S = sign flag (bit 7; NS if not set)
>
>My guesses is the same, but the problem for me is how to read the value.of
>the vaarious flags.
>
>> Not sure about these:
>>
>> UP = ???
>> NO = presumably overflow flag (bit 11)
>> NIO = probably IOPL flag (I/O privileg level, bit 13)

UP/DN - Direction for REP STOSB / REP STOSW, etc.

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