Hi,
For a few days I’m a fresh user of an LPC2148 testboard. I’ve got some programming experience on AVR, but I’m new to ARM. I’ve got a problem with an sprintf() function. Everything works fine with a code:
int a=2;
char buf[16];
sprintf(buf, "A: %d", a);
LCDWrite(buf);
I’ve got a “A: 2” on a LCD. But when I try to use double/float variables:
double a=2;
char buf[16];
sprintf(buf, "A: %0.2lf", a);
LCDWrite(buf);
there’s nothing on a LCD, program seems to halt (no intruction is being made after sprintf()). Can anyone help me?
These are my syscalls.c i startup.s files:
#include <sys/types.h>
#include <sys/stat.h>
#include <errno.h>
#include "uart.h"
#undef errno
extern int errno;
caddr_t _sbrk(int incr)
{
extern char _end; /* Defined by the linker */
extern char _ram_end;
static char *heap_end;
char *prev_heap_end;
if(heap_end == 0)
{
heap_end = &_end;
}
prev_heap_end = heap_end;
if(heap_end + incr > (char*)&_ram_end)
{
errno = ENOMEM;
return (caddr_t) -1;
}
heap_end += incr;
return (caddr_t) prev_heap_end;
}
int _isatty(int fd)
{
return 1;
}
int _lseek(int fd, off_t pos, int whence)
{
return 0;
}
int _close(int file) {
return -1;
}
int _read(int fd, void *buffer, unsigned int count)
{
return(0);
}
int _fstat(int file, struct stat *st) {
st->st_mode = S_IFCHR;
return 0;
}
int open(const char *name, int flags, int mode) {
return -1;
}
int
_write(int file, char *ptr, int len) {
int todo;
for (todo = 0; todo < len; todo++) {
UART_PutChar((*ptr++));
}
return len;
}
/* ***************************************************************************************************************
crt.s STARTUP ASSEMBLY CODE
-----------------------
Module includes the interrupt vectors and start-up code.
*************************************************************************************************************** */
/* Stack Sizes */
.set UND_STACK_SIZE, 0x00000200
.set ABT_STACK_SIZE, 0x00000200
.set FIQ_STACK_SIZE, 0x00000200
.set IRQ_STACK_SIZE, 0x00000200
.set SVC_STACK_SIZE, 0x00000200
#.set _MEMMAP, 0xE01FC040
/* Standard definitions of Mode bits and Interrupt (I & F) flags in PSRs (program status registers) */
.set MODE_USR, 0x10 /* Normal User Mode */
.set MODE_FIQ, 0x11 /* FIQ Processing Fast Interrupts Mode */
.set MODE_IRQ, 0x12 /* IRQ Processing Standard Interrupts Mode */
.set MODE_SVC, 0x13 /* Supervisor Processing Software Interrupts Mode */
.set MODE_ABT, 0x17 /* Abort Processing memory Faults Mode */
.set MODE_UND, 0x1B /* Undefined Processing Undefined Instructions Mode */
.set MODE_SYS, 0x1F /* System Running Priviledged Operating System Tasks Mode */
.set I_BIT, 0x80 /* when I bit is set, IRQ is disabled (program status registers) */
.set F_BIT, 0x40 /* when F bit is set, FIQ is disabled (program status registers) */
.text
.arm
.global Reset_Handler
.global _startup
.func _startup
_startup:
# Exception Vectors
_vectors: ldr PC, Reset_Addr
ldr PC, Undef_Addr
ldr PC, SWI_Addr
ldr PC, PAbt_Addr
ldr PC, DAbt_Addr
nop /* Reserved Vector (holds Philips ISP checksum) */
ldr PC, [PC,#-0xFF0] /* see page 71 of "Insiders Guide to the Philips ARM7-Based Microcontrollers" by Trevor Martin */
ldr PC, FIQ_Addr
Reset_Addr: .word Reset_Handler /* defined in this module below */
Undef_Addr: .word UNDEF_Routine /* defined in main.c */
SWI_Addr: .word SWI_Routine /* defined in main.c */
PAbt_Addr: .word UNDEF_Routine /* defined in main.c */
DAbt_Addr: .word UNDEF_Routine /* defined in main.c */
IRQ_Addr: .word IRQ_Routine /* defined in main.c */
FIQ_Addr: .word FIQ_Routine /* defined in main.c */
.word 0 /* rounds the vectors and ISR addresses to 64 bytes total */
Reset_Handler:
/* Setup a stack for each mode - note that this only sets up a usable stack
for User mode. Also each mode is setup with interrupts initially disabled. */
ldr r0, =_stack_end
msr CPSR_c, #MODE_UND|I_BIT|F_BIT /* Undefined Instruction Mode */
mov sp, r0
sub r0, r0, #UND_STACK_SIZE
msr CPSR_c, #MODE_ABT|I_BIT|F_BIT /* Abort Mode */
mov sp, r0
sub r0, r0, #ABT_STACK_SIZE
msr CPSR_c, #MODE_FIQ|I_BIT|F_BIT /* FIQ Mode */
mov sp, r0
sub r0, r0, #FIQ_STACK_SIZE
msr CPSR_c, #MODE_IRQ|I_BIT|F_BIT /* IRQ Mode */
mov sp, r0
sub r0, r0, #IRQ_STACK_SIZE
msr CPSR_c, #MODE_SVC|I_BIT|F_BIT /* Supervisor Mode */
mov sp, r0
sub r0, r0, #SVC_STACK_SIZE
msr CPSR_c, #MODE_SYS|I_BIT|F_BIT /* User Mode */
mov sp, r0
/* copy .data section (Copy from ROM to RAM) */
ldr R1, =_text_end
ldr R2, =_data_start
ldr R3, =_data_end
1: cmp R2, R3
ldrlo R0, [R1], #4
strlo R0, [R2], #4
blo 1b
/* Clear .bss section (Zero init) */
mov R0, #0
ldr R1, =_bss_start
ldr R2, =_bss_end
2: cmp R1, R2
strlo R0, [R1], #4
blo 2b
/* Enter the C code */
b main
.endfunc
.end
Kulesz
Maybe it can be set in the makefile somehow?