PEEK and POKE Library: Difference between revisions
Jump to navigation
Jump to search
Code by Michael Calkins
Note: These functions and statements use a variable name reference pointer in memory instead of DEF SEG.
Navigation:
Main Page with Articles and Tutorials
Keyword Reference - Alphabetical
Keyword Reference - By usage
Report a broken link
No edit summary |
No edit summary |
||
(3 intermediate revisions by the same user not shown) | |||
Line 28: | Line 28: | ||
{*(unsigned long int *)p = n;}</nowiki> | {*(unsigned long int *)p = n;}</nowiki> | ||
{{TextEnd}} | {{TextEnd}} | ||
{{ | {{Small|Code by Michael Calkins}} | ||
''PeekPoke.BAS'' | ''PeekPoke.BAS'' | ||
Line 36: | Line 36: | ||
' public domain, sept 2011, michael calkins | ' public domain, sept 2011, michael calkins | ||
{{Cl|DECLARE | {{Cl|DECLARE LIBRARY|DECLARE CUSTOMTYPE LIBRARY}} "peekpoke" | ||
{{Cl|FUNCTION}} peekb~%% ({{Cl|BYVAL}} p {{Cl|AS}} {{Cl|_UNSIGNED}} {{Cl|_OFFSET}}) 'Byte | {{Cl|FUNCTION}} peekb~%% ({{Cl|BYVAL}} p {{Cl|AS}} {{Cl|_UNSIGNED}} {{Cl|_OFFSET}}) 'Byte | ||
{{Cl|FUNCTION}} peekw~% ({{Cl|BYVAL}} p {{Cl|AS}} {{Cl|_UNSIGNED}} {{Cl|_OFFSET}}) 'Integer(Word) | {{Cl|FUNCTION}} peekw~% ({{Cl|BYVAL}} p {{Cl|AS}} {{Cl|_UNSIGNED}} {{Cl|_OFFSET}}) 'Integer(Word) | ||
Line 77: | Line 77: | ||
{{PageSeeAlso}} | |||
* [[DECLARE LIBRARY]] | * [[DECLARE LIBRARY]] | ||
* [[PEEK]], [[POKE]] | * [[PEEK]], [[POKE]] |
Latest revision as of 23:01, 27 February 2024
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 https://www.tapatalk.com/groups/qbasic/viewtopic.php?p=188921#p188921 */ 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;} |
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 |
See also