TellyMate Etch-A-Sketch

#define CHAR_ESC "\x1B"

int x;
int y;

void setup()
{
  Serial.begin(57600); // set to 57600 baud
  screen_clear();
  cursor_show(false);
}

void loop()
{
  x = map(analogRead(0), 0, 1023, 0, 25); // determine x from the pot
  y = map(analogRead(1), 0, 1023, 0, 38); // determine y from the pot
  cursor_move( x , y ) ; // move to those coordinates
  Serial.print( '\xDB' ) ; // draw a block

}

// Helper functions from the TellyMate example code:

void cursor_move( uint8_t row , uint8_t col )
{ // <ESC>Yrc
  Serial.print( CHAR_ESC "Y" ) ;
  Serial.print((unsigned char)(32 + row)) ;
  Serial.print((unsigned char)(32 + col)) ;
}

void cursor_show( bool show )
{ // <ESC>e or <ESC>f
  Serial.print( CHAR_ESC ) ;
  Serial.print( show?'e':'f' ) ;
}

void screen_clear( void )
{ // <ESC>E
  Serial.print( CHAR_ESC "E" );
}