Revision 1443
1. Alpha code to trigger the new wireless bootloader from the user program. Not tested
Includes subroutine in the XBee library to reset the XBee's settings
2. New subroutine in the BOM library to more accurately estimate the position of the max reading using weighted average of the readings instead of max reading.
Also roughly estimates distance to BOM-detected robot based on signal strength
| bom.c | ||
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return lowest_i; |
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else |
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return -1; |
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} |
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/** |
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* Computes the weighted average of all the bom readings to estimate the position (and distance) of another robot. |
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* |
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* @pre must call bom refresh |
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* @param dist pointer to int in which to return the estimated distance to the other robot |
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* @return estimated position of the max bom value element as a fixed point value analogous to 10 times the |
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* index of the max bom value. -1 if no value is lower than BOM_VALUE_THRESHOLD. |
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**/ |
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int bom_get_max10(int *dist) {
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int i, max; |
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long long mean, sum; |
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max = bom_get_max(); |
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if (max < 0) |
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{
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if (dist) |
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{
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*dist = -1; |
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} |
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return -1; |
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} |
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/* Record values into an array */ |
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for (i = 0; i < NUM_BOM_LEDS; i++) {
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int idx = ((i + (NUM_BOM_LEDS/2 - max) + NUM_BOM_LEDS) % NUM_BOM_LEDS) - (NUM_BOM_LEDS/2 - max); |
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int val = 255 - bom_val[i]; |
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mean += idx * val; |
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sum += val; |
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} |
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mean = (mean * 10) / sum; |
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mean = (mean + NUM_BOM_LEDS*10) % (NUM_BOM_LEDS*10); |
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if (dist) |
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{
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*dist = 50 - sum/48; |
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} |
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return mean; |
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} |
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/** |
Also available in: Unified diff