Thermistor config

configtool/thermistortablefile.py

@@ -54,6 +54,7 @@ def generateTempTables(sensors, settings):
 
   ofp.output("#define NUMTABLES %d" % len(tl))
   ofp.output("#define NUMTEMPS %d" % N)
+  ofp.output("#define TEMPTABLE_FORMAT 1")
   ofp.output("");
 
   for i in range(len(tl)):
@@ -65,7 +66,7 @@ def generateTempTables(sensors, settings):
     ofp.close();
     return True
 
-  ofp.output("const uint16_t PROGMEM temptable[NUMTABLES][NUMTEMPS][2] = {")
+  ofp.output("const uint16_t PROGMEM temptable[NUMTABLES][NUMTEMPS][3] = {")
 
   tcount = 0
   for tn in tl:
@@ -102,8 +103,9 @@ def BetaTable(ofp, params, names, settings, finalTable):
 
   samples = optimizeTempTable(thrm, N, hiadc)
 
+  prev = samples[0]
   for i in samples:
-    t = int(thrm.temp(i))
+    t = thrm.temp(i)
     if t is None:
       ofp.output("// ERROR CALCULATING THERMISTOR VALUES AT ADC %d" % i)
       continue
@@ -117,10 +119,12 @@ def BetaTable(ofp, params, names, settings, finalTable):
       c = " "
     else:
       c = ","
-    ostr = ("    {%4s, %5s}%s // %4d C, %6.0f ohms, %0.3f V,"
-            " %0.2f mW") % (i, t * 4, c, t, int(round(r)),
-            vTherm, ptherm * 1000)
+    delta = (t-thrm.temp(prev))/(prev-i) if i!=prev else 0
+    ostr = ("    {%4s, %5s, %5s}%s // %4d C, %6.0f ohms, %0.3f V,"
+            " %0.2f mW, m=%0.4f") % (i, int(t * 4), int(delta*4*256), c,
+            int(t), int(round(r)), vTherm, ptherm * 1000, delta)
     ofp.output(ostr)
+    prev = i
 
   if finalTable:
     ofp.output("  }")
@@ -145,8 +149,9 @@ def SteinhartHartTable(ofp, params, names, settings, finalTable):
 
   samples = optimizeTempTable(thrm, N, hiadc)
 
+  prev = samples[0]
   for i in samples:
-    t = int(thrm.temp(i))
+    t = thrm.temp(i)
     if t is None:
       ofp.output("// ERROR CALCULATING THERMISTOR VALUES AT ADC %d" % i)
       continue
@@ -157,8 +162,10 @@ def SteinhartHartTable(ofp, params, names, settings, finalTable):
       c = " "
     else:
       c = ","
-    ofp.output("    {%4d, %5d}%s // %4d C, %6d ohms" %
-               (i, t * 4, c, t, int(round(r))))
+    delta = (t-thrm.temp(prev))/(prev-i) if i!=prev else 0
+    ofp.output("    {%4d, %5d, %5d}%s // %4d C, %6d ohms, m=%0.4f" %
+               (i, int(t * 4), int(delta*4*256), c, int(t), int(round(r))), delta)
+    prev = i
 
   if finalTable:
     ofp.output("  }")

simulator.h

@@ -142,6 +142,7 @@ void sim_error(const char msg[]);
 void sim_assert(bool cond, const char msg[]);
 void sim_gcode_ch(char ch);
 void sim_gcode(const char msg[]);
+void sim_report_temptables(int sensor) ;
 
 /**
  * Initialize simulator timer and set time scale.

simulator/analog_sim.c

@@ -1,15 +1,41 @@
+#include "temp.h"
 #include "analog.h"
 #include "simulator.h"
+#include <stdio.h>
 
 static bool analog_initialised = false;
 
 void analog_init(void) {
-  sim_info("analog_init: not implemented in simulator");
   analog_initialised = true;
 }
 
+static uint16_t analog_read_value = 0;
 uint16_t analog_read(uint8_t channel) {
   sim_assert(analog_initialised, "analog_init() was not called before analog_read()");
   sim_assert(sim_interrupts, "interrupts disabled");
-  return 0;
+  return analog_read_value;
+}
+
+void sim_report_temptables(int sensor) {
+  int i ;
+  temp_sensor_t s, first = sensor, last = sensor+1 ;
+
+  // sensor is a specific sensor or -1 for "all sensors"
+  if (sensor == -1) {
+    first = 0;
+    last = NUM_TEMP_SENSORS;
+  }
+
+  sei();
+  analog_init();
+  printf("; Temperature sensor test %d\n", sensor);
+  for (s = first; s < last; s++ ) {
+    printf("; Sensor %d\n", s);
+    for (i = 0 ; i < 1024 ; i++ ) {
+      analog_read_value = i ;
+      temp_sensor_tick() ;
+      uint16_t temp = temp_get(s);
+      printf("%d %.2f\n", i, ((float)temp)/4 ) ;
+    }
+  }
 }

simulator/simulator.c

@@ -45,14 +45,15 @@ int verbose = 1;                ///< 0=quiet, 1=normal, 2=noisy, 3=debug, etc.
 int trace_gcode = 0;            ///< show gcode on the console
 int trace_pos = 0;              ///< show print head position on the console
 
-const char * shortopts = "qgpvt:o::";
+const char * shortopts = "qgpvt:o::T::";
 struct option opts[] = {
   { "quiet", no_argument, &verbose , 0 },
   { "verbose", no_argument, NULL, 'v' },
   { "gcode", no_argument, NULL, 'g' },
   { "pos", no_argument, NULL, 'p' },
   { "time-scale", required_argument, NULL, 't' },
   { "tracefile", optional_argument, NULL, 'o' },
+  { "report-temptable", optional_argument, NULL, 'T' },
   { 0, 0, 0, 0 }
 };
 
@@ -65,6 +66,7 @@ static void usage(const char *name) {
   printf("   -p || --pos                   show head position on console\n");
   printf("   -t || --time-scale=n          set time-scale; 0=warp-speed, 1=real-time, 2=half-time, etc.\n");
   printf("   -o || --tracefile[=filename]  write simulator pin trace to 'outfile' (default filename=datalog.out)\n");
+  printf("   -T || --report-temptable=n    Report calculated temperatures for all ADC values and exit\n");
   printf("\n");
   exit(1);
 }
@@ -96,6 +98,9 @@ void sim_start(int argc, char** argv) {
     case 'o':
       recorder_init(optarg ? optarg : "datalog.out");
       break;
+    case 'T':
+      sim_report_temptables(optarg ? atoi(optarg) : -1);
+      exit(0);
     default:
       exit(1);
     }

temp.c

@@ -186,53 +186,64 @@ static uint16_t mcp3008_read(uint8_t channel) {
 */
 #if defined TEMP_THERMISTOR || defined TEMP_MCP3008
 static uint16_t temp_table_lookup(uint16_t temp, uint8_t sensor) {
-  uint8_t j;
+  uint8_t lo, hi;
   uint8_t table_num = temp_sensors[sensor].additional;
 
-  for (j = 1; j < NUMTEMPS; j++) {
-    if (pgm_read_word(&(temptable[table_num][j][0])) > temp) {
-
-      if (DEBUG_PID && (debug_flags & DEBUG_PID))
-        sersendf_P(PSTR("pin:%d Raw ADC:%d table entry: %d"),
-                   temp_sensors[sensor].temp_pin, temp, j);
-
-      // Wikipedia's example linear interpolation formula.
-      // y = ((x - x₀)y₁ + (x₁-x)y₀) / (x₁ - x₀)
-      // y = temp
-      // x = ADC reading
-      // x₀= temptable[j-1][0]
-      // x₁= temptable[j][0]
-      // y₀= temptable[j-1][1]
-      // y₁= temptable[j][1]
-      temp = (
-      // ((x - x₀)y₁
-        ((uint32_t)temp - pgm_read_word(&(temptable[table_num][j-1][0]))) *
-                          pgm_read_word(&(temptable[table_num][j][1]))
-      //             +
-        +
-      //               (x₁-x)y₀)
-        (pgm_read_word(&(temptable[table_num][j][0])) - (uint32_t)temp) *
-          pgm_read_word(&(temptable[table_num][j - 1][1])))
-      //                        /
-        /
-      //                          (x₁ - x₀)
-        (pgm_read_word(&(temptable[table_num][j][0])) -
-         pgm_read_word(&(temptable[table_num][j - 1][0])));
-
-      if (DEBUG_PID && (debug_flags & DEBUG_PID))
-        sersendf_P(PSTR(" temp:%d.%d"), temp / 4, (temp % 4) * 25);
-
-      // Value found, no need to read the table further.
-      break;
-    }
+  // Binary search for table value bigger than our target
+  for (lo = 0, hi=NUMTEMPS-1 ; hi-lo > 1 ; ) {
+    uint8_t j = lo + (hi - lo) / 2 ;
+    if (pgm_read_word(&(temptable[table_num][j][0])) >= temp)
+      hi = j ;
+    else
+      lo = j ;
   }
+  //   lo = index of highest entry less than target
+  //   hi = index of lowest entry greater than or equal to target
 
   if (DEBUG_PID && (debug_flags & DEBUG_PID))
-    sersendf_P(PSTR(" Sensor:%d\n"), sensor);
+    sersendf_P(PSTR("pin:%d Raw ADC:%d table entry: %d"),
+               temp_sensors[sensor].temp_pin, temp, hi);
+
+  #if (TEMPTABLE_FORMAT == 0)
+    // Wikipedia's example linear interpolation formula.
+    // y = ((x - x₀)y₁ + (x₁-x)y₀) / (x₁ - x₀)
+    // y = temp
+    // x = ADC reading
+    // x₀= temptable[lo][0]
+    // x₁= temptable[hi][0]
+    // y₀= temptable[lo][1]
+    // y₁= temptable[hi][1]
+    temp = (
+    // ((x - x₀)y₁
+      ((uint32_t)temp - pgm_read_word(&(temptable[table_num][lo][0]))) *
+                        pgm_read_word(&(temptable[table_num][hi][1]))
+    //             +
+      +
+    //               (x₁-x)y₀)
+      (pgm_read_word(&(temptable[table_num][hi][0])) - (uint32_t)temp) *
+        pgm_read_word(&(temptable[table_num][lo][1])))
+    //                        /
+      /
+    //                          (x₁ - x₀)
+      (pgm_read_word(&(temptable[table_num][hi][0])) -
+       pgm_read_word(&(temptable[table_num][lo][0])));
+    #elif (TEMPTABLE_FORMAT == 1)
+      // Linear interpolation using pre-computed slope
+      // y = y₁ - (x-x₁)*d₁
+      #define X1 pgm_read_word(&(temptable[table_num][hi][0]))
+      #define Y1 pgm_read_word(&(temptable[table_num][hi][1]))
+      #define D1 pgm_read_word(&(temptable[table_num][hi][2]))
+
+      temp = Y1 - ((((int32_t)temp - X1) * D1 + (1<<7)) >> 8);
+    #else
+      #error "temptable format unrecognized"
+    #endif
+
+  if (DEBUG_PID && (debug_flags & DEBUG_PID))
+    sersendf_P(PSTR(" temp:%d.%d"), temp / 4, (temp % 4) * 25);
 
-  // Clamp for overflows.
-  if (j == NUMTEMPS)
-    temp = temptable[table_num][NUMTEMPS - 1][1];
+  if (DEBUG_PID && (debug_flags & DEBUG_PID))
+    sersendf_P(PSTR(" Sensor:%d\n"), sensor);
 
   return temp;
 }