Faster (bisect) search in thermistor tables (#10883)
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		| @@ -937,17 +937,25 @@ void Temperature::manage_heater() { | ||||
| #define TEMP_AD595(RAW)  ((RAW) * 5.0 * 100.0 / 1024.0 / (OVERSAMPLENR) * (TEMP_SENSOR_AD595_GAIN) + TEMP_SENSOR_AD595_OFFSET) | ||||
| #define TEMP_AD8495(RAW) ((RAW) * 6.6 * 100.0 / 1024.0 / (OVERSAMPLENR) * (TEMP_SENSOR_AD8495_GAIN) + TEMP_SENSOR_AD8495_OFFSET) | ||||
|  | ||||
| #define SCAN_THERMISTOR_TABLE(TBL,LEN) do{                          \ | ||||
|   for (uint8_t i = 1; i < LEN; i++) {                               \ | ||||
|     const short entry10 = (short)pgm_read_word(&TBL[i][0]);         \ | ||||
|     if (entry10 > raw) {                                            \ | ||||
|       const short entry00 = (short)pgm_read_word(&TBL[i-1][0]),     \ | ||||
|                   entry01 = (short)pgm_read_word(&TBL[i-1][1]),     \ | ||||
|                   entry11 = (short)pgm_read_word(&TBL[i][1]);       \ | ||||
|       return entry01 + (raw - entry00) * float(entry11 - entry01) / float(entry10 - entry00); \ | ||||
|     }                                                               \ | ||||
|   }                                                                 \ | ||||
|   return (short)pgm_read_word(&TBL[LEN-1][1]);                      \ | ||||
| /** | ||||
|  * Bisect search for the range of the 'raw' value, then interpolate | ||||
|  * proportionally between the under and over values. | ||||
|  */ | ||||
| #define SCAN_THERMISTOR_TABLE(TBL,LEN) do{                             \ | ||||
|   uint8_t l = 0, r = LEN, m;                                           \ | ||||
|   for (;;) {                                                           \ | ||||
|     m = (l + r) >> 1;                                                  \ | ||||
|     if (m == l || m == r) return (short)pgm_read_word(&TBL[LEN-1][1]); \ | ||||
|     short v00 = pgm_read_word(&TBL[m-1][0]),                           \ | ||||
|           v10 = pgm_read_word(&TBL[m-0][0]);                           \ | ||||
|          if (raw < v00) r = m;                                         \ | ||||
|     else if (raw > v10) l = m;                                         \ | ||||
|     else {                                                             \ | ||||
|       const short v01 = (short)pgm_read_word(&TBL[m-1][1]),            \ | ||||
|                   v11 = (short)pgm_read_word(&TBL[m-0][1]);            \ | ||||
|       return v01 + (raw - v00) * float(v11 - v01) / float(v10 - v00);  \ | ||||
|     }                                                                  \ | ||||
|   }                                                                    \ | ||||
| }while(0) | ||||
|  | ||||
| // Derived from RepRap FiveD extruder::getTemperature() | ||||
|   | ||||
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