Hallo,
was ist dem an dem Code Falsch?
Als Compiler verwnde ich WinAvr
1 | #include <avr/io.h>
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2 |
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3 | #define USART_BAUDRATE 9600
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4 | #define BAUD_PRESCALE (((F_CPU / (USART_BAUDRATE * 16UL))) - 1)
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5 |
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6 | int main (void)
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7 | {
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8 | char ReceivedByte;
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9 |
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10 | UCSRB |= (1 << RXEN) | (1 << TXEN); // Turn on the transmission and reception circuitry
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11 | UCSRC |= (1 << URSEL) | (1 << UCSZ0) | (1 << UCSZ1); // Use 8-bit character sizes
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12 |
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13 | UBRRL = BAUD_PRESCALE; // Load lower 8-bits of the baud rate value into the low byte of the UBRR register
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14 | UBRRH = (BAUD_PRESCALE >> 8); // Load upper 8-bits of the baud rate value into the high byte of the UBRR register
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15 |
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16 | for (;;) // Loop forever
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17 | {
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18 | while ((UCSRA & (1 << RXC)) == 0) {}; // Do nothing until data have been recieved and is ready to be read from UDR
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19 | ReceivedByte = UDR; // Fetch the recieved byte value into the variable "ByteReceived"
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20 |
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21 | while ((UCSRA & (1 << UDRE)) == 0) {}; // Do nothing until UDR is ready for more data to be written to it
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22 | UDR = ReceivedByte; // Echo back the received byte back to the computer
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23 | }
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24 | }
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Als Fehlermeldung erhalte ich:
main.c:10: error: 'UCSRB' undeclared (first use in this function)
main.c:10: error: (Each undeclared identifier is reported only once
main.c:10: error: for each function it appears in.)
main.c:11: error: 'UCSRC' undeclared (first use in this function)
main.c:11: error: 'URSEL' undeclared (first use in this function)
main.c:13: error: 'UBRRL' undeclared (first use in this function)
main.c:14: error: 'UBRRH' undeclared (first use in this function)
main.c:18: error: 'UCSRA' undeclared (first use in this function)
main.c:19: error: 'UDR' undeclared (first use in this function)
Und zwar immer wenn ich den USART beutzen möcht auch bei anderen Codes.
mfg alex
