Hi there,

i'm testing a MicroChip PIC32 EV-board connected to a new Riverdi 7" 1024x600 EVE4 BT817 display.
I'm using the EVE library from Rudolph.

So far everything is OK and all works fine.

To test out the limits i wrote a small test routine which writes zigzag lines in blocks of 250 single lines.

The BT817Q spec says display list size is 8k, but i crash after the 4k border:


void test_8k(void) {
   
   uint16_t  i;

   EVE_cmd_dl( CMD_DLSTART );               
   EVE_cmd_dl( CLEAR( 1, 1, 1 ) );
   
num_dl_static = EVE_memRead16(REG_CMD_DL);         // read current position

   EVE_color_rgb( WHITE );                         // sets the foreground color   
   EVE_cmd_dl( LINE_WIDTH( 1 * 16 ) );
   
  // *** draw zigzag 1
 
  EVE_cmd_dl( BEGIN(EVE_LINE_STRIP) );

   for( i = 0 ; i < 250 ; i++ ) {
      
      if( i % 2 )
      EVE_cmd_dl( VERTEX2F( 1600 + i*40,  66*16 -50 *16 ) );
      else
      EVE_cmd_dl( VERTEX2F( 1600 + i*40,  66*16 +50 *16 ) );

     
// to go sure
    if( i % 50 )
       EVE_execute_cmd();      
   }


num_dl_static = EVE_memRead16(REG_CMD_DL);         // read current position
      
  // *** draw zigzag 2
 
  EVE_cmd_dl( BEGIN(EVE_LINE_STRIP) );
   
   for( i = 0 ; i < 250 ; i++ ) {
      
      if( i % 2 )
      EVE_cmd_dl( VERTEX2F( 1600 + i*40,  196*16 -50 *16 ) );
      else
      EVE_cmd_dl( VERTEX2F( 1600 + i*40,  196*16 +50 *16 ) );
      
// to go sure
    if( i % 50 )
      EVE_execute_cmd();      
   }
   
num_dl_static = EVE_memRead16(REG_CMD_DL);         // read current position

  // *** draw zigzag 3
 
  EVE_cmd_dl( BEGIN(EVE_LINE_STRIP) );
   
   for( i = 0 ; i < 250 ; i++ ) {
      
      if( i % 2 )
      EVE_cmd_dl( VERTEX2F( 1600 + i*40,  326*16 -50 *16 ) );
      else
      EVE_cmd_dl( VERTEX2F( 1600 + i*40,  326*16 +50 *16 ) );
      
// to go sure
    if( i % 50 )
      EVE_execute_cmd();      
   }

num_dl_static = EVE_memRead16(REG_CMD_DL);         // read current position

  // *** draw zigzag 4
 
  EVE_cmd_dl( BEGIN(EVE_LINE_STRIP) );
   
//   for( i = 0 ; i < 250 ; i++ ) {   // CRASHES !
   for( i = 0 ; i < 230 ; i++ ) {   // OK
      
      if( i % 2 )
      EVE_cmd_dl( VERTEX2F( 1600 + i*40,  456*16 -50 *16 ) );
      else
      EVE_cmd_dl( VERTEX2F( 1600 + i*40,  456*16 +50 *16 ) );
      
// to go sure
    if( i % 50 )
      EVE_execute_cmd();      
   }

  // *** draw zigzag 5
 
//  EVE_cmd_dl( BEGIN(EVE_LINE_STRIP) );
//   
////   for( i = 0 ; i < 250 ; i++ ) {   // CRASHES !
//   for( i = 0 ; i < 230 ; i++ ) {
//      
//      if( i % 2 )
//      EVE_cmd_dl( VERTEX2F( 1600 + i*40,  586*16 -50 *16 ) );//
//      else
//        EVE_cmd_dl( VERTEX2F( 1600 + i*40,  586*16 +50 *16 ) );
//      
//    if( i % 50 )
//      EVE_execute_cmd();      
//   }

num_dl_static = EVE_memRead16(REG_CMD_DL);   

   EVE_cmd_dl( END() );
  EVE_cmd_dl( DL_DISPLAY );   
  EVE_cmd_dl( CMD_SWAP );     
  EVE_execute_cmd();
}



One picture shows the forth block with 230 lines, the second one with 250 line, which crashes.

"num_dl_static" shows the size of the display list to me in the debugger.

What am i doing i wrong ?