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mija |
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/* mija 2008 |
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source file for hw USART ATtiny2313 |
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fixed boud rate 9600 8N1 |
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PD1 - TX |
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PD0 - RX |
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ver.: 0.0 TESTED |
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*/ |
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#include <avr/io.h> |
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#include "rs232.h" |
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//************************************************************** |
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void rs232_init(void) |
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{ |
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//set baud rate fixed 9600 8N1 |
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UCSRA = UCSRA | ( 1 << U2X) ; |
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UBRRH = 0; |
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UBRRL = 12; |
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//enable RX TX |
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UCSRB = (1<<RXEN)|(1<<TXEN); |
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//8N1 |
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//UCSRC = (1<<UMSEL); |
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} |
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int rs232_put(char data) |
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{ |
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// Wait for empty transmit buffer |
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while ( !( UCSRA & (1<<UDRE)) ); |
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// Put data into buffer, sends the data |
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UDR = data; |
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return 0; |
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} |
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int rs232_get(void) |
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{ |
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// Wait for data to be received |
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while ( !(UCSRA & (1<<RXC)) ); |
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// Get and return received data from buffer |
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return UDR; |
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} |
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