Pololu 0J5840, Руководство пользователя

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if (power_difference < 0)
set_motors(mapower_difference, max_speed);
else
set_motors(max_speed, max_speed-power_difference);
}
// A global ring buffer for data coming in. This is used by the
// read_next_byte() and previous_byte() functions, below.
char buffer[100];
// A pointer to where we are reading from.
unsigned char read_index = 0;
// Waits for the next byte and returns it. Runs play_check to keep
// the music playing and serial_check to keep receiving bytes.
// Calls pid_check() to keep following the line.
char read_next_byte()
{
while (serial_get_received_bytes() == read_index)
{
serial_check();
play_check();
// pid_check takes some time; only run it if we don't
// have more bytes to process
if (serial_get_received_bytes() == read_index)
pid_check();
}
char ret = buffer[read_index];
read+;
if (read_index >= 100)
read_index = 0;
return ret;
}
// Backs up by one byte in the ring buffer.
void previous_byte()
{
read_index --;
if (read_index == 255)
read_index = 99;
}
// Returns true if and only if the byte is a command byte (>= 0x80).
char is_command( char byte)
{
if (byte < 0)
return 1;
return 0;
}
// Returns true if and only if the byte is a data byte (< 0x80).
char is_data( char byte)
{
if (byte < 0)
return 0;
return 1;
}
// If it's not a data byte, beeps, backs up one, and returns true.
Pololu 3pi Robot User’s Guide © 2001–2019 Pololu Corporation
10. Expansion Information Page 69 of 85