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Functions with multiple long params

I've created a little test program that runs fine in the simulator, but causes the hardware (80C390) to reset when a function with multiple long parameters is called. This is with v6.22. Am I missing something obvious? Running in the large memory model in a new project (I.E. all other settings as defaults.)

#include <REG390.H>
#include <absacc.h>

#include <stdio.h> 

void wait (void)  {                   /* wait function */
  int i;
  for (i=0;i<20000;i++)
  {
    ;
  }
}
void Serial0_Initialize(void)
{
  //  init serial interface 38400 baud @ 20MHz
  PCON  |= 0x80;   /* Double serial port 0 baud rate */
  SCON0  = 0x50;   /* Async receiver serial port 0 enable */	         
  TMOD  |= 0x21;   /* Timer 0 16 bits, Timer 1 8 bits with auto reload mode */        
  TH1    = 0xF8;   /* Load MSB of Timer 1 */
  CKCON |= 0x10;   /* Timer 1 clock select divide by 4 of xtal freq */
  TCON   = 0x50;   /* Timer 0 run enable, Timer 1 run enable */           
  TI     = 1;      /* Serial port 0 transmitter interrupt flag set */
}

unsigned char xdata* egdBufferGetInt(int buffer, int width, int height, int depth)
{
  unsigned char xdata *curBuf = 0;

  return curBuf;
}

unsigned char xdata* egdBufferGet(long buffer, long width, long height, long depth)
{
  unsigned char xdata *curBuf = 0;

  return curBuf;
}

long egdDrawInt(unsigned char xdata *buffer, int width, int height)
{
  ;
}

long egdDraw(unsigned char xdata *buffer, long width, long height)
{
  ;
}

void main (void)
{
  unsigned char xdata *b;

  // Initialize serial port 0
  Serial0_Initialize();
  printf("Serial initialized!\n");
  wait();

  printf("Trying BufferGetInt...\n");
  b=egdBufferGetInt(0, 320, 240, 1);
  printf("BufferGetInt success\n");
  wait();

  printf("Trying BufferGet...\n");
  b=egdBufferGet(0, 320, 240, 1);
  printf("BufferGet success\n");
  wait();

  printf("Trying Draw Int...\n");
  egdDrawInt(b, 320, 240);
  printf("Draw Int success\n");
  wait();

  printf("Trying Draw...\n");
  egdDraw(b, 320, 240);
  printf("Draw success\n");
  wait();

  while (1)
  {
    printf("Waiting...\n");
    wait();
  }
}

Here is the output from the serial port:
Serial initialized!
Trying BufferGetInt...
BufferGetInt success
Trying BufferGet...
 erial initialized!
Trying BufferGetInt...
BufferGetInt success
Trying BufferGet...
 erial initialized!
Trying BufferGetInt...
BufferGetInt success
Trying BufferGet...
 erial initialized!
Trying BufferGetInt...
BufferGetInt success
Trying BufferGet...
 erial initialized!

Parents
  • I wouldn't guarantee I tried making them all longs for this particular example, but I have tried it on others, without any help.

    In fact, I've noticed even making more than 2 local variables longs with a function that takes a long usually causes problems.

    I'm not setting up the watchdog, so that shouldn't be a problem either.

    We are planning on moving to the contiguous memory model anyway, so I hope this problem will go away there, but I haven't tested that theory yet.

    Unfortunately I don't have any hardware other than the 80C390 to test on.

Reply
  • I wouldn't guarantee I tried making them all longs for this particular example, but I have tried it on others, without any help.

    In fact, I've noticed even making more than 2 local variables longs with a function that takes a long usually causes problems.

    I'm not setting up the watchdog, so that shouldn't be a problem either.

    We are planning on moving to the contiguous memory model anyway, so I hope this problem will go away there, but I haven't tested that theory yet.

    Unfortunately I don't have any hardware other than the 80C390 to test on.

Children
  • Can you try it in v6.14 of the compiler?

    I know that the "upgrade" from v6.14 to v6.20 broke one of my functions with long parameters, although v6.22 has fixed that particular problem for me.

  • Unfortunately no, since we just recently purchased the compiler.

    I'd be curious if the test program runs on other hardware fine, since it runs in the simulator fine...

  • Hmm... two long args (8 bytes) causes problems. Interesting that passing two longs in registers would require the entire register bank. I wonder if there is a "spill over" bug. When a stack frame cannot fit into the arg. regs. then they must spill over into a stack frame memory area.

    In the short term, you might create a suitcase union of structs such that you have in it structs for both long an int vars and a type field. Then have one function that looks at the type field and does the correct work.

    Or you could write a var_args function and make your function work like printf which does work.

    - Mark

  • "it runs in the simulator fine..."

    Probably not the same thing then; in my case, the compiler was definitely generating bad code - the fault could be seen on both target and simulator.