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test.c
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test.c
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#include <pololu/orangutan.h>
/*
* serial1: for the Orangutan LV, SV, SVP, X2, Baby-O and 3pi robot.
*
* This example listens for bytes on PD0/RXD. Whenever it receives a byte, it
* performs a custom action. Whenever the user presses the middle button, it
* transmits a greeting on PD1/TXD.
*
* The Baby Orangutan does not have a green LED, LCD, or pushbuttons so
* that part of the code will not work.
*
* To make this example compile for the Orangutan SVP or X2, you
* must add a first argument of UART0 to all the serial_* function calls
* to receive on PD0/RXD0 and transmit on PD1/TXD0.
*
* http://www.pololu.com/docs/0J20
* http://www.pololu.com
* http://forum.pololu.com
*/
// receive_buffer: A ring buffer that we will use to receive bytes on PD0/RXD.
// The OrangutanSerial library will put received bytes in to
// the buffer starting at the beginning (receiveBuffer[0]).
// After the buffer has been filled, the library will automatically
// start over at the beginning.
char receive_buffer[32];
// receive_buffer_position: This variable will keep track of which bytes in the receive buffer
// we have already processed. It is the offset (0-31) of the next byte
// in the buffer to process.
unsigned char receive_buffer_position = 0;
// send_buffer: A buffer for sending bytes on PD1/TXD.
char send_buffer[32];
// wait_for_sending_to_finish: Waits for the bytes in the send buffer to
// finish transmitting on PD1/TXD. We must call this before modifying
// send_buffer or trying to send more bytes, because otherwise we could
// corrupt an existing transmission.
void wait_for_sending_to_finish()
{
while(!serial_send_buffer_empty());
}
// process_received_byte: Responds to a byte that has been received on
// PD0/RXD. If you are writing your own serial program, you can
// replace all the code in this function with your own custom behaviors.
void process_received_byte(char byte)
{
switch(byte)
{
// If the character 'G' is received, turn on the green LED.
case 'G':
green_led(1);
break;
// If the character 'g' is received, turn off the green LED.
case 'g':
green_led(0);
break;
// If the character 'c' is received, play the note c.
case 'c':
play_from_program_space(PSTR("c16"));
break;
// If the character 'd' is received, play the note d.
case 'd':
play_from_program_space(PSTR("d16"));
break;
// If any other character is received, change its capitalization and
// send it back.
default:
wait_for_sending_to_finish();
send_buffer[0] = byte ^ 0x20;
serial_send(send_buffer, 1);
break;
}
}
void check_for_new_bytes_received()
{
while(serial_get_received_bytes() != receive_buffer_position)
{
// Process the new byte that has just been received.
process_received_byte(receive_buffer[receive_buffer_position]);
// Increment receive_buffer_position, but wrap around when it gets to
// the end of the buffer.
if (receive_buffer_position == sizeof(receive_buffer)-1)
{
receive_buffer_position = 0;
}
else
{
receive_buffer_position++;
}
}
}
int main()
{
// Set the baud rate to 9600 bits per second. Each byte takes ten bit
// times, so you can get at most 960 bytes per second at this speed.
serial_set_baud_rate(9600);
// Start receiving bytes in the ring buffer.
serial_receive_ring(receive_buffer, sizeof(receive_buffer));
while(1)
{
// Deal with any new bytes received.
check_for_new_bytes_received();
// If the user presses the middle button, send "Hi there!"
// and wait until the user releases the button.
if (button_is_pressed(MIDDLE_BUTTON))
{
wait_for_sending_to_finish();
memcpy_P(send_buffer, PSTR("Hi there!\r\n"), 11);
serial_send(send_buffer, 11);
// Wait for the user to release the button. While the processor is
// waiting, the OrangutanSerial library will take care of receiving
// bytes using the serial reception interrupt. But if enough bytes
// arrive during this period to fill up the receive_buffer, then the
// older bytes will be lost and we won't know exactly how many bytes
// have been received.
wait_for_button_release(MIDDLE_BUTTON);
}
}
}