Stefan Kalscheuer
61c131486b
* renamed methods and fields using camelCase notation * merged nested if-statements * removed unused globals
64 lines
1.2 KiB
C
64 lines
1.2 KiB
C
/**
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* MIDI Footswitch
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*
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* @file main.h
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* @author Stefan Kalscheuer
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* @date 2014-06-17
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* @brief USART helper funcitons
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*/
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/**
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* Initialize USART interface with given BAUD rate.
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*
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* @param baud Baud rate.
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* @return void
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*/
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void USART_Init(uint32_t baud) {
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/* Calculate UBRR */
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uint16_t ubrr_val = (uint16_t) ((F_CPU / (baud * 16L)) - 1);
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/* Set baud rate */
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UBRRH = (uint8_t) (ubrr_val >> 8);
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UBRRL = (uint8_t) ubrr_val;
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/* Enable transmitter */
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UCSRB |= (1 << TXEN);
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/* Set frame format: 8data, 1stop bit */
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UCSRC = (3 << UCSZ0);
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}
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/**
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* Receive USART data from buffer.
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*
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* @return Data byte from buffer.
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*/
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unsigned char USART_Receive(void) {
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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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/**
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* Transmit USART data byte.
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*
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* @param data Data byte to transmit.
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* @return void
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*/
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void USART_Transmit(uint8_t data) {
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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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}
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/**
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* Flush USART buffer.
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*
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* @return void
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*/
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void USART_Flush(void) {
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uint8_t dummy;
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while (UCSRA & (1 << RXC)) {
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dummy = UDR;
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}
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}
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