RE: [avr-gcc-list] Newbie Problems

[Rune Christensen]

Hello

If you want to read sensor_temp1 in SIGNAL(SIG_OVERFLOW0)
and use it in main loop then I will use this method

volatile unsigned char sensor_temp1;

SIGNAL{SIG_OVERFLOW0}
{
  ...
  sensortemp1 = PIND & 0x7c // direct register access is possible in avr-gcc
from version 3.2
  ...
}

void main(void)
{
  ...
  cli();
  unsigned char temp = sensor_temp1;
  sei();
  ...
}

or

void main(void)
{
  ...
  unsigned char sreg = SREG;
  cli();
  unsigned char temp = sensor_temp1;
  SREG = sreg;
  ...
}


Happy New Year

Rune

> -----Original Message-----
> From: address@hidden [mailto:address@hidden
> Behalf Of Panther Electronics
> Sent: Monday, December 30, 2002 10:46 AM
> To: address@hidden
> Subject: [avr-gcc-list] Newbie Problems
>
>
> Hi,
>
> Can i get some explanation of the warning while compiling.
>
> WARNING: 'sensor_temp1' has no address in mapfile.
> WARNING: 'sensor_temp2' has no address in mapfile.
> WARNING: 'sw_temp1' has no address in mapfile.
> WARNING: 'sw_temp2' has no address in mapfile.
>
> the above variables are local to tim0 overflow; the values of
> sensor_temp1 and sensor_temp2 is 0x00; that would mean that the
> variable value is lost on exit? what am i doing wrong?
>
> ---code--
>
> SIGNAL(SIG_OVERFLOW0)        /* signal handler for tcnt0 overflow
> interrupt */
> {
>   static unsigned char sensor_temp1, sensor_temp2;
>   static unsigned char sw_temp1, sw_temp2;
> /*
>     outp(~led, PORTB);       /* invert the output since a zero
> means: LED on
>     led <<= 1;               /* move to next LED
>     if (!led)                /* overflow: start with Port B0 again
>         led = 1;
>     */
>     outp(0x00, TCNT0);          /* reset counter to get this
> interrupt again */
>     if ( timers_1 )
>         -- timers_1;
>     if ( timers_2 )
>         -- timers_2;
>
>     if ( db_1 == db )
>     {
>         sensor_temp2 =  inp(PIND) & 0x7c;         /* 0x7c = &b0111_1100 */
>         /* the balance code */
>     }
>     else
>     {
>         if ( bit_is_set( flag_1, in_flag_1 ) == 0 )
>         {
>             if ( bit_is_set( flag_1, sensor_in ) == 0 )
>             {
>                 sensor_temp1 = ( inp(PIND) & 0x7c );
>                 sbi ( flag_1, in_flag_1 );
>                 db_1 = 0;
>             }
>         }
>         else
>             ++ db_1;
>     }
>
> --- compiler snap shot ----
> avr-gcc --version
> avr-gcc (GCC) 3.3 20021209 (experimental)
> Copyright (C) 2002 Free Software Foundation, Inc.
> This is free software; see the source for copying conditions.  There is NO
> warranty; not even for MERCHANTABILITY or FITNESS FOR A
> PARTICULAR PURPOSE.
>
> "Size before:"
>   text           data            bss            dec            
> hex        filename
>    0           1760              0           1760            6e0  
>       First.hex
> avr-gcc -c -g -Os -funsigned-char -funsigned-bitfields
> -fpack-struct -fshort-enums -Wall -Wstrict-prototypes
> -Wa,-ahlms=First.lst -mmcu=at90s8515 -I. First.c -o First.o
> avr-gcc -Wl,-Map=First.map,--cref -mmcu=at90s8515 First.o    -lm
> --output First.elf
> avr-objcopy -O ihex -R .eeprom First.elf First.hex
> avr-objcopy -j .eeprom --set-section-flags=.eeprom="alloc,load"
> --change-section-lma .eeprom=0 -O ihex First.elf First.eep
> objtool loadelf First.elf mapfile First.map writecof First.cof
> WARNING: 'sensor_temp1' has no address in mapfile.
> WARNING: 'sensor_temp2' has no address in mapfile.
> WARNING: 'sw_temp1' has no address in mapfile.
> WARNING: 'sw_temp2' has no address in mapfile.
> "Size after:"
>   text           data            bss            dec            
> hex        filename
>    0           1762              0           1762            6e2  
>       First.hex
> "--------  end  --------"
> "Errors: none"
> >Exit code: 0
>
> thanks in advance
>
> Srikanth Kamath T
>
>
>
> avr-gcc-list at http://avr1.org
>

avr-gcc-list at http://avr1.org