Pololu 3pi Robot - Manual (Page 54)

void do_play()
{
unsigned char tune_length = read_next_byte();
if(check_data_byte(tune_length))
return;
unsigned char i;
for(i=0;i<tune_length;i++)
{
if(i > sizeof(music_buffer)) // avoid overflow
return;
music_buffer[i] = read_next_byte();
if(check_data_byte(music_buffer[i]))
return;
}
// add the end of string character 0
music_buffer[i] = 0;
play(music_buffer);
}
// Clears the LCD
void do_clear()
{
clear();
}
// Displays data to the screen
void do_print()
{
unsigned char string_length = read_next_byte();
if(check_data_byte(string_length))
return;
unsigned char i;
for(i=0;i<string_length;i++)
{
unsigned char character;
character = read_next_byte();
if(check_data_byte(character))
return;
// Before printing to the LCD we need to go to AUTOMATIC mode.
// Otherwise, we might miss characters during the lengthy LCD routines.
serial_set_mode(SERIAL_AUTOMATIC);
print_character(character);
serial_set_mode(SERIAL_CHECK);
}
}
// Goes to the x,y coordinates on the lcd specified by the two data bytes
void do_lcd_goto_xy()
{
unsigned char x = read_next_byte();
if(check_data_byte(x))
return;
unsigned char y = read_next_byte();
if(check_data_byte(y))
return;
lcd_goto_xy(x,y);
}
// Runs through an automatic calibration sequence
void auto_calibrate()
{
time_reset();
set_motors(60, -60);
while(get_ms() < 250)
calibrate_line_sensors(IR_EMITTERS_ON);
Pololu 3pi Robot User's Guide © 2001–2014 Pololu Corporation
10. Expansion Information Page 54 of 63