Timer

Simple sample to show you how to init and use timer.

Using library

GP2X minimal library by rlyeh, 2005

License

• Free for non-commercial projects (it would be nice receiving a mail from you).  Other cases, ask me first.
• GamePark Holdings is not allowed to use this library and/or use parts from it.

Source code

#include "minimal.h"

int main(int argc, char *argv[])
{
 gp2x_init(1000, 16, 11025,16,1,60, 1);

 while(1)
 {
  static unsigned char color=0x00;
  unsigned long pad=gp2x_joystick_read();

  if(pad & GP2X_VOL_DOWN) if(pad & GP2X_START) exit(0);

  //wait one second
  gp2x_timer_delay(1000);

  //invert the screen
  memset(gp2x_video_RGB[0].screen16, color^=0xFF, 320*240*2);

  //output the elapsed ticks
  gp2x_printf(NULL, 0,0, "one second passed away... %lu\n",gp2x_timer_read());

  //update changes
  gp2x_video_RGB_flip(0);
 }
}

void gp2x_sound_frame(void *blah, void *buff, int samples) { }

Explanation

• Our gp2x_init line inits the whole library.  We set 1000 ticks per second, 8 bits video mode, 11025/16bits/stereo/60Hz sound mode, and solid font.
• Our gp2x_timer_delay line reads the joystick.  In this case we do a loop until any press is found.
• Our gp2x_printf and gp2x_timer_read line displays the elapsed time in gp2x_ticks since the last gp2x_init call.
• Our gp2x_video_RGB_flip line updates the whole screen and sets up the next hidden screen area.
• Our gp2x_sound_frame line fills our sound buffer.  Note that this function will not generate any sound since we have written a void function.

C Compilation

arm-linux-gcc minimal.c 1second.c -static -lpthread -lm

C++ Compilation

arm-linux-g++ minimal.c 1second.c -static -lpthread -lm

Output

• this program changes the screen color every second, and writes a text line to the active linux console.
• press volume down and start buttons to exit.