gnupic: Questions about SDCC PIC code gen
Subject:
Re: Questions about SDCC PIC code gen
From:
Rick Mann ####@####.####
Date:
22 Oct 2002 04:22:05 -0000
Message-Id: <B9DA1EDC.E731%rmann@latencyzero.com>
on 10/21/02 7:27 PM, matt at ####@####.#### wrote:
> Can you give us, say, the 5 preceding assembly instructions and the 5
> following. Thanks.
Sure! I only limited it because it was on a different computer, and I was
typing it all in. Here's the actual code, copy/pasted. I've put both the C
and the ASM, but I left out all of the equates. BTW, I also don't get proper
code for setting the global gIRState variable.
-----------------------
#include "p16f877.h"
typedef unsigned char UInt8;
void InitPorts();
UInt8 gIRState = 0;
void
main()
{
InitPorts();
PORTD = 0xA;
}
void
InitPorts()
{
// Clear GIE
do
{
GIE = 0;
} while (GIE != 0);
TRISD = 0;
// Clear all our program registers
gIRState = 1;
}
-----------------------
ORG 0
;--------------------------------------------------------
; interrupt vector
;--------------------------------------------------------
; .area CSEG (CODE)
;__interrupt_vect:
; ljmp __sdcc_gsinit_startup
; reti
; .ds 7
; reti
; .ds 7
; reti
; .ds 7
; reti
; .ds 7
; reti
; .ds 7
; reti
; .ds 7
;--------------------------------------------------------
; global & static initialisations
;--------------------------------------------------------
; .area GSINIT (CODE)
; .area GSFINAL (CODE)
; .area GSINIT (CODE)
__sdcc_gsinit_startup:
; .area GSFINAL (CODE)
; ljmp __sdcc_program_startup
;--------------------------------------------------------
; code
;--------------------------------------------------------
; .area CSEG (CODE)
;***
; pBlock Stats: dbName = D
;***
;; Starting pCode block
;***
; pBlock Stats: dbName = M
;***
;entry: _main ;Function start
; 2 exit points
;has an exit
;functions called:
; _InitPorts
; _InitPorts
;; Starting pCode block
_main ;Function start
; 2 exit points
;#CSRC test.c 16
; InitPorts();
CALL _InitPorts
;#CSRC test.c 17
; PORTD = 0xA;
MOVLW 0x0a
MOVWF _PORTD
RETURN
; exit point of _main
;***
; pBlock Stats: dbName = C
;***
;entry: _InitPorts ;Function start
; 2 exit points
;has an exit
;; Starting pCode block
_InitPorts ;Function start
; 2 exit points
;#CSRC test.c 27
; GIE = 0;
BCF (_GIE >> 3), (_GIE & 7)
BSF _STATUS,5
;#CSRC test.c 30
; TRISD = 0;
CLRF _TRISD
;#CSRC test.c 34
; gIRState = 1;
MOVLW 0x01
BCF _STATUS,5
RETURN
; exit point of _InitPorts
end
--
Rick
