Sensor 502 and PTC cleanup

Marlin/Configuration.h

@@ -373,6 +373,7 @@
  *     4 : 10k thermistor !! do not use it for a hotend. It gives bad resolution at high temp. !!
  *     5 : 100K thermistor - ATC Semitec 104GT-2/104NT-4-R025H42G (Used in ParCan, J-Head, and E3D) (4.7k pullup)
  *   501 : 100K Zonestar (Tronxy X3A) Thermistor
+ *   502 : 100K Zonestar Thermistor used by hot bed in Zonestar Prusa P802M
  *   512 : 100k RPW-Ultra hotend thermistor (4.7k pullup)
  *     6 : 100k EPCOS - Not as accurate as table 1 (created using a fluke thermocouple) (4.7k pullup)
  *     7 : 100k Honeywell thermistor 135-104LAG-J01 (4.7k pullup)

Marlin/Configuration_adv.h

@@ -1666,33 +1666,33 @@
     // Probe temperature calibration generates a table of values starting at PTC_SAMPLE_START
     // (e.g. 30), in steps of PTC_SAMPLE_RES (e.g. 5) with PTC_SAMPLE_COUNT (e.g. 10) samples.
 
-    // #define PTC_SAMPLE_START  30.0f
-    // #define PTC_SAMPLE_RES    5.0f
-    // #define PTC_SAMPLE_COUNT  10U
+    //#define PTC_SAMPLE_START  30.0f
+    //#define PTC_SAMPLE_RES    5.0f
+    //#define PTC_SAMPLE_COUNT  10U
 
     // Bed temperature calibration builds a similar table.
 
-    // #define BTC_SAMPLE_START  60.0f
-    // #define BTC_SAMPLE_RES    5.0f
-    // #define BTC_SAMPLE_COUNT  10U
+    //#define BTC_SAMPLE_START  60.0f
+    //#define BTC_SAMPLE_RES    5.0f
+    //#define BTC_SAMPLE_COUNT  10U
 
     // The temperature the probe should be at while taking measurements during bed temperature
     // calibration.
-    // #define BTC_PROBE_TEMP 30.0f
+    //#define BTC_PROBE_TEMP 30.0f
 
     // Height above Z=0.0f to raise the nozzle. Lowering this can help the probe to heat faster.
     // Note: the Z=0.0f offset is determined by the probe offset which can be set using M851.
-    // #define PTC_PROBE_HEATING_OFFSET 0.5f
+    //#define PTC_PROBE_HEATING_OFFSET 0.5f
 
     // Height to raise the Z-probe between heating and taking the next measurement. Some probes
     // may fail to untrigger if they have been triggered for a long time, which can be solved by
     // increasing the height the probe is raised to.
-    // #define PTC_PROBE_RAISE 15U
+    //#define PTC_PROBE_RAISE 15U
 
     // If the probe is outside of the defined range, use linear extrapolation using the closest
     // point and the PTC_LINEAR_EXTRAPOLATION'th next point. E.g. if set to 4 it will use data[0]
     // and data[4] to perform linear extrapolation for values below PTC_SAMPLE_START.
-    // #define PTC_LINEAR_EXTRAPOLATION 4
+    //#define PTC_LINEAR_EXTRAPOLATION 4
   #endif
 #endif