Article View: comp.sys.ibm.pc
Article #42727Re: POKE, PEEK, FAR POINTER
From: Kaleb Keithley
Date: Tue, 20 Feb 1990 23:46
Date: Tue, 20 Feb 1990 23:46
28 lines
1435 bytes
1435 bytes
In article <8389@cg-atla.UUCP> fredex@cg-atla.UUCP (Fred Smith) writes:
>In article <848@dukempd.phy.duke.edu> fang@dukempd.phy.duke.edu (Fang Zhong) writes:
>> Here is something I have tried and it did not work.
>> unsigned far *addr;
>> unsigned seg, offset, byte;
>
>> addr = NULL;
>> addr += seg*16 + offset;
>> *addr = byte;
>MIcrosoft C has a pair of macros called FP_SEG and FP_OFF which are
>FP_SEG(addr) = (segment value);
>FP_OFF(addr) = (offset value);
Another way to set a far * is as follows
assuming, say you want to look at VGA screen memory at A000:0000
unsigned far *addr;
addr = (unsigned far *)A0000000;
I always thought the FP_SEG and FP_OFF macros were to get the segment/offset
components from some initialized far pointer.
Chewey, get us outta here!
kaleb@mars.jpl.nasa.gov Jet Propeller Labs
Kaleb Keithley
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arc1-ca.pugleaf.net!utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!samsung!usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov!kalebReferences:
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Path: arc1-ca.pugleaf.net!utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!samsung!usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov!kaleb From: kaleb@mars.jpl.nasa.gov (Kaleb Keithley) Newsgroups: comp.sys.ibm.pc Subject: Re: POKE, PEEK, FAR POINTER Keywords: ON a AT with Microsoft C Message-ID: <2886@jato.Jpl.Nasa.Gov> Date: 20 Feb 90 23:46:13 GMT References: <848@dukempd.phy.duke.edu> <8389@cg-atla.UUCP> Sender: news@jato.Jpl.Nasa.Gov Reply-To: kaleb@mars.UUCP (Kaleb Keithley) Organization: Jet Propulsion Laboratory, Pasadena, CA. Lines: 28