PEEK and POKE Library

From QB64 Wiki
Revision as of 16:59, 19 December 2011 by imported>Clippy
Jump to navigation Jump to search

This header allows you to peek and poke bytes, words, and dwords in QB64. The functions seem to work okay when used with signed variables also. For example, I am able to assign the return of peekw~% to an INTEGER without problem. Regards, Michael Calkins


Create PeekPoke.h text file in the QB64 folder:

/* peek and poke for bytes, words, and dwords in qb64 public domain, sept 2011, michael calkins http://www.network54.com/Forum/648955/message/1315950606/ */ unsigned char peekb(void * p) {return *(unsigned char *)p;} unsigned short int peekw(void * p) {return *(unsigned short int *)p;} unsigned long int peekd(void * p) {return *(unsigned long int *)p;} void pokeb(void * p, unsigned char n) {*(unsigned char *)p = n;} void pokew(void * p, unsigned short int n) {*(unsigned short int *)p = n;} void poked(void * p, unsigned long int n) {*(unsigned long int *)p = n;}

Public domain, Sept 2011, Michael Calkins

PeekPoke.BAS

' peek and poke for bytes, words, and dwords in qb64 ' requires peekpoke.h ' public domain, sept 2011, michael calkins DECLARE CUSTOMTYPE LIBRARY "peekpoke" FUNCTION peekb~%% (BYVAL p AS _UNSIGNED _OFFSET) 'Byte FUNCTION peekw~% (BYVAL p AS _UNSIGNED _OFFSET) 'Integer(Word) FUNCTION peekd~& (BYVAL p AS _UNSIGNED _OFFSET) 'Long(Dword) SUB pokeb (BYVAL p AS _UNSIGNED _OFFSET, BYVAL n AS _UNSIGNED _BYTE) SUB pokew (BYVAL p AS _UNSIGNED _OFFSET, BYVAL n AS _UNSIGNED INTEGER) SUB poked (BYVAL p AS _UNSIGNED _OFFSET, BYVAL n AS _UNSIGNED LONG) END DECLARE ' examples: DIM buffer AS STRING * 16 DIM ptr AS _UNSIGNED _OFFSET buffer = "abcd---- i-ptrs" ptr = _OFFSET(buffer) PRINT buffer pokeb ptr + &HA, &H3 PRINT buffer pokew ptr + 5, &H3FA8 PRINT buffer poked ptr + 4, &HDBB2B1B0 PRINT buffer poked ptr, CVL("QB64") poked ptr + 4, &H2020011A PRINT buffer PRINT "0x" + HEX$(peekb~%%(ptr + 1)) PRINT "0x" + HEX$(peekw~%(ptr + 2)) PRINT "0x" + HEX$(peekd~&(ptr + 9)) END

Note: These functions and statements use a reference variable name instead of DEF SEG.


See also:



Navigation:
Keyword Reference - Alphabetical
Keyword Reference - By Usage
Main Wiki Page