This file is a replacement for the Microchip MPLAB-C18 library's 'memcpy' function.
It takes advantage of my 'generic pointer' implementation, which may copy from both RAM or ROM (FLASH) to RAM.
The Macros and definitions needed to use the 'generic pointers' are located in the file "genericpointer.h".
Usage example:
#include "genericpointer.h" void RAM *memcpy( void RAM *dst, const void GENERIC *src, size_t n ); char Buffer[32]; const char ROM Msg1[] = "This message is in ROM"; char RAM Msg2[] = "This message is in RAM."; char GENERIC *pMsg; void SomeFunction( const char GENERIC *p ) { // 'p' is already a generic pointer. memcpy( Buffer, p, sizeof Buffer ); // A rom pointer is essentially a generic pointer. memcpy( Buffer, Msg1, sizeof Buffer ); // A ram pointer needs to be converted. memcpy( Buffer, MAKE_GEN_PTR_RAM( Msg2 ), sizeof Buffer ); // Direct conversion. pMsg = Msg1; // Conversion needed. pMsg = MAKE_GEN_PTR_RAM( Msg2 ); // A generic pointer may point to RAM or ROM. if( IS_GEN_PTR_TO_RAM( pMsg )) // We will write through it only if it points to RAM. memcpy( (char RAM*)pMsg, p, 16 ); }
This code works only in extended mode.
;=============================================================================== ; Copyright (c) 2007-2008, Isaac Marino Bavaresco ; All rights reserved. ; ; Redistribution and use in source and binary forms, with or without ; modification, are permitted provided that the following conditions are met: ; * Redistributions of source code must retain the above copyright ; notice, this list of conditions and the following disclaimer. ; * Neither the name of the author nor the ; names of its contributors may be used to endorse or promote products ; derived from this software without specific prior written permission. ; ; THIS SOFTWARE IS PROVIDED BY THE AUTHOR ''AS IS'' AND ANY ; EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED ; WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE ; DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY ; DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES ; (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; ; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ; ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT ; (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS ; SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. ;=============================================================================== ; isaacbavaresco@yahoo.com.br ;=============================================================================== #include <P18CXXX.INC> ;=============================================================================== radix decimal ;=============================================================================== STRING CODE ;=============================================================================== n equ 0 src equ 2 dst equ 5 ; void RAM *memcpy( void RAM *dst, const void GENERIC *src, size_t n ) global memcpy ; { memcpy: movff FSR2L,POSTINC1 ; *FSR1++ = FSR2; movff FSR2H,POSTINC1 movff FSR1L,FSR2L ; FSR2 = FSR1; movff FSR1H,FSR2H subfsr 2,9 ; FSR2 -= 9; movf [dst+0],w ; PROD = FSR0 = dst; movwf FSR0L,ACCESS movwf PRODL,ACCESS movf [dst+1],w movwf FSR0H,ACCESS movwf PRODH,ACCESS ;------------------------------------------------------------------------------- rlcf [src+2],w ; if( (unsigned short long)src & 0x800000UL ) bnc InROM ; { ;------------------------------------------------------------------------------- InRAM: movsf [n+0],TBLPTRL ; TBLPTR = n; movsf [n+1],TBLPTRH movf [src+0],w ; FSR2 = src; movsf [src+1],FSR2H movwf FSR2L,ACCESS bra InRAMStart ; while( TBLPTR-- ) InRAMLoop: movff POSTINC2,POSTINC0 ; *FSR0++ = *FSR2++; InRAMStart: movlw 0 decf TBLPTRL,f,ACCESS subwfb TBLPTRH,f,ACCESS bc InRAMLoop bra Epilog ; } ;------------------------------------------------------------------------------- ; else ; { InROM: movsf [src+0],TBLPTRL ; TBLPTR = src; movsf [src+1],TBLPTRH movsf [src+2],TBLPTRU bra InROMStart ; while( n-- ) InROMLoop: tblrd *+ ; *FSR0++ = *TBLPTR++; movff TABLAT,POSTINC0 InROMStart: movlw 0 decf [n+0],f subwfb [n+1],f bc InROMLoop ; } ;------------------------------------------------------------------------------- Epilog: subfsr 1,1 ; FSR2 = *--FSR1; movff POSTDEC1,FSR2H movff INDF1,FSR2L return 0 ; } ;=============================================================================== end ;===============================================================================
file: /Techref/member/IMB-yahoo-J86/memcpy.asm.htm, 5KB, , updated: 2010/4/14 14:12, local time: 2024/11/26 22:30,
owner: IMB-yahoo-J86,
3.142.136.210:LOG IN
|
©2024 These pages are served without commercial sponsorship. (No popup ads, etc...).Bandwidth abuse increases hosting cost forcing sponsorship or shutdown. This server aggressively defends against automated copying for any reason including offline viewing, duplication, etc... Please respect this requirement and DO NOT RIP THIS SITE. Questions? <A HREF="http://techref.massmind.org/Techref/member/IMB-yahoo-J86/memcpy.asm.htm"> memcpy.asm: Implementation of 'memcpy' for Microchip MPLAB-C18 with support for 'generic pointers'</A> |
Did you find what you needed? |