main
Line | |
---|
1 | /* AVR USART acces functions - stolen from Extreme Electronics */
|
---|
2 |
|
---|
3 | #include <avr/io.h>
|
---|
4 | #include <inttypes.h>
|
---|
5 |
|
---|
6 | #ifndef BAUD
|
---|
7 | #error You must define BAUD to use libuart.
|
---|
8 | #endif
|
---|
9 |
|
---|
10 | //This function is used to initialize the USART
|
---|
11 | void USARTInit()
|
---|
12 | {
|
---|
13 | //Set Baud rate
|
---|
14 | #include <util/setbaud.h>
|
---|
15 | UBRRH = UBRRH_VALUE;
|
---|
16 | UBRRL = UBRRL_VALUE;
|
---|
17 | #if USE_2X
|
---|
18 | UCSRA |= (1 << U2X);
|
---|
19 | #else
|
---|
20 | UCSRA &= ~(1 << U2X);
|
---|
21 | #endif
|
---|
22 |
|
---|
23 | /*Set Frame Format
|
---|
24 | >> Asynchronous mode
|
---|
25 | >> No Parity
|
---|
26 | >> 1 StopBit
|
---|
27 | >> char size 8
|
---|
28 | */
|
---|
29 | #ifdef __AVR_ATtiny2313__
|
---|
30 | UCSRC = (1 << UCSZ1) | (1 << UCSZ0);
|
---|
31 | #else
|
---|
32 | UCSRC = (1 << URSEL) | (3 << UCSZ0);
|
---|
33 | #endif
|
---|
34 |
|
---|
35 | //Enable The receiver and transmitter
|
---|
36 | UCSRB = (1 << RXEN) | (1 << TXEN);
|
---|
37 | }
|
---|
38 |
|
---|
39 |
|
---|
40 | //This fuction writes the given "data" to
|
---|
41 | //the USART which then transmit it via TX line
|
---|
42 | void USARTWriteChar(char data)
|
---|
43 | {
|
---|
44 | //Wait untill the transmitter is ready
|
---|
45 | while(!(UCSRA & (1<<UDRE)))
|
---|
46 | {
|
---|
47 | //Do nothing
|
---|
48 | }
|
---|
49 |
|
---|
50 | //Now write the data to USART buffer
|
---|
51 |
|
---|
52 | UDR=data;
|
---|
53 | }
|
---|
54 |
|
---|
55 |
|
---|
56 | //This function is used to read the available data
|
---|
57 | //from USART. This function will wait untill data is
|
---|
58 | //available.
|
---|
59 | char USARTReadChar()
|
---|
60 | {
|
---|
61 | //Wait untill a data is available
|
---|
62 | while(!(UCSRA & (1<<RXC)))
|
---|
63 | {
|
---|
64 | //Do nothing
|
---|
65 | }
|
---|
66 |
|
---|
67 | //Now USART has got data from host
|
---|
68 | //and is available is buffer
|
---|
69 |
|
---|
70 | return UDR;
|
---|
71 | }
|
---|
72 |
|
---|
73 |
|
---|
74 | void USARTWriteHex(unsigned char i)
|
---|
75 | {
|
---|
76 | unsigned char k = i>>4;
|
---|
77 | if (k <=9) k+='0';
|
---|
78 | else k+=('A'-10);
|
---|
79 |
|
---|
80 | USARTWriteChar(k);
|
---|
81 |
|
---|
82 | k = i&0xF;
|
---|
83 | if (k <=9) k+='0';
|
---|
84 | else k+=('A'-10);
|
---|
85 |
|
---|
86 | USARTWriteChar(k);
|
---|
87 | }
|
---|
Note:
See
TracBrowser
for help on using the repository browser.