Revision 677
encoder: added data array buffer and accumulators
| encoders.c | ||
|---|---|---|
| 10 | 10 |
unsigned short int left_data; |
| 11 | 11 |
unsigned short int right_data; |
| 12 | 12 |
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| 13 |
RING_BUFFER_NEW(enc_buffer, BUFFER_SIZE, short int); |
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| 13 |
unsigned short int left_data_array[BUFFER_SIZE]; |
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| 14 |
unsigned short int right_data_array[BUFFER_SIZE]; |
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| 15 |
int left_data_idx; |
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| 16 |
int right_data_idx; |
|
| 14 | 17 |
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| 18 |
int left_dx; |
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| 19 |
int right_dx; |
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| 20 |
long int timecount; |
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| 21 |
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| 22 |
void encoder_recv(char data); |
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| 23 |
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| 24 |
//Helper Function Prototypes |
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| 25 |
inline void left_data_array_put(unsigned short int value); |
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| 26 |
inline unsigned short int left_data_array_top(void); |
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| 27 |
inline unsigned short int left_data_array_prev(void); |
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inline unsigned short int left_data_array_bottom(void); |
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| 29 |
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inline void right_data_array_put(unsigned short int value); |
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inline unsigned short int right_data_array_top(void); |
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inline unsigned short int right_data_array_prev(void); |
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inline unsigned short int right_data_array_bottom(void); |
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//RING_BUFFER_NEW(enc_buffer, BUFFER_SIZE, short int); |
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| 36 |
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| 15 | 37 |
void encoders_init(void){
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| 38 |
int i; |
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| 39 |
|
|
| 16 | 40 |
spi_init(encoder_recv); |
| 17 | 41 |
buf_index = 0; |
| 18 | 42 |
left_data_buf = 0; |
| 19 | 43 |
right_data_buf= 0; |
| 20 | 44 |
left_data = -1; |
| 21 | 45 |
right_data = -1; |
| 22 |
RING_BUFFER_INIT(enc_buffer,BUFFER_SIZE); |
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| 46 |
//RING_BUFFER_INIT(enc_buffer,BUFFER_SIZE); |
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| 47 |
left_data_idx = 0; |
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| 48 |
right_data_idx = 0; |
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for(i = 0; i < BUFFER_SIZE; i++) {
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| 50 |
left_data_array[i] = 0; |
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} |
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for(i = 0; i < BUFFER_SIZE; i++) {
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right_data_array[i] = 0; |
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} |
|
| 23 | 55 |
} |
| 24 | 56 |
|
| 25 | 57 |
int encoder_read(char encoder){
|
| ... | ... | |
| 38 | 70 |
return 0; |
| 39 | 71 |
} |
| 40 | 72 |
|
| 73 |
int encoder_get_dx(char encoder) {
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| 74 |
if(encoder==LEFT) |
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return left_dx; |
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else if(encoder==RIGHT) |
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return right_dx; |
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| 78 |
else return -1; |
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} |
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| 80 |
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| 81 |
void encoder_rst_dx(char encoder) {
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if(encoder==LEFT) |
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left_dx = 0; |
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else if(encoder==RIGHT) |
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right_dx = 0; |
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| 86 |
} |
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| 87 |
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| 88 |
int encoder_get_tc(void) {
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return timecount; |
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| 90 |
} |
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| 91 |
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void encoder_rst_tc(void) {
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timecount = 0; |
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} |
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| 96 |
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| 41 | 98 |
//Full reads occur every 40 microseconds. This function should be called |
| 42 | 99 |
//every 8 microseconds. |
| 43 | 100 |
void encoder_recv(char data){
|
| 101 |
short int dx; |
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| 102 |
|
|
| 44 | 103 |
if(buf_index < 2) |
| 45 | 104 |
right_data_buf |= (((short)data) << ((1-buf_index)*8)) & (0xFF<<(1-buf_index)); |
| 46 | 105 |
|
| ... | ... | |
| 78 | 137 |
left_data_buf = 0; |
| 79 | 138 |
right_data_buf = 0; |
| 80 | 139 |
} |
| 140 |
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| 141 |
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| 142 |
if(left_data < INVALID) {
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//Put new data onto data array |
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left_data_array_put(left_data); |
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| 145 |
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//Adjust left accumulator |
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dx = left_data - left_data_array_prev(); |
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if(dx > 5) { //underflow
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| 149 |
left_dx += dx - 1023; |
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} |
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else if(dx < -5) { //overflow
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left_dx += dx + 1023; |
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} |
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else {
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left_dx += dx; |
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} |
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} |
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| 158 |
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if(right_data < INVALID) {
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//Put new data onto data array |
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right_data_array_put(right_data); |
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| 162 |
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//Adjust right accumulator |
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dx = right_data - right_data_array_prev(); |
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if(dx > 5) { //underflow
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right_dx += dx - 1023; |
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} |
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else if(dx < -5) { //overflow
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right_dx += dx + 1023; |
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} |
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else {
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right_dx += dx; |
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} |
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} |
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| 175 |
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//Increment timecount accumulator |
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timecount++; |
|
| 81 | 178 |
} |
| 179 |
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| 180 |
//Helper Functions |
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inline void left_data_array_put(unsigned short int value) {
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if(left_data_idx == BUFFER_SIZE-1) |
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left_data_idx = 0; |
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else |
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left_data_idx++; |
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left_data_array[left_data_idx] = value; |
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} |
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inline unsigned short int left_data_array_top(void) {
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return left_data_array[left_data_idx]; |
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} |
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inline unsigned short int left_data_array_prev(void) {
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if(left_data_idx == 0) |
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return left_data_array[BUFFER_SIZE-1]; |
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else |
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return left_data_array[left_data_idx - 1]; |
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} |
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inline unsigned short int left_data_array_bottom(void) {
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if(left_data_idx == BUFFER_SIZE-1) |
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return left_data_array[0]; |
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else |
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return left_data_array[left_data_idx + 1]; |
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} |
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inline void right_data_array_put(unsigned short int value) {
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if(right_data_idx == BUFFER_SIZE-1) |
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right_data_idx = 0; |
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else |
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right_data_idx++; |
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right_data_array[right_data_idx] = value; |
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} |
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inline unsigned short int right_data_array_top(void) {
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return right_data_array[right_data_idx]; |
|
| 217 |
} |
|
| 218 |
|
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| 219 |
inline unsigned short int right_data_array_prev(void) {
|
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| 220 |
if(right_data_idx == 0) |
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return right_data_array[BUFFER_SIZE-1]; |
|
| 222 |
else |
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return right_data_array[right_data_idx - 1]; |
|
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} |
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|
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inline unsigned short int right_data_array_bottom(void) {
|
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if(right_data_idx == BUFFER_SIZE-1) |
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return right_data_array[0]; |
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else |
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return right_data_array[right_data_idx + 1]; |
|
| 231 |
} |
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