From 8b011b8773c3ca52ddb57affdb113607940bc0eb Mon Sep 17 00:00:00 2001
From: AnHardt <github@kitelab.de>
Date: Thu, 12 Mar 2020 02:33:56 +0100
Subject: [PATCH] Add Selftest

Using code from #5
---
 Adafruit_MAX31865.cpp | 19 +++++++++++++++++++
 Adafruit_MAX31865.h   |  2 ++
 2 files changed, 21 insertions(+)

diff --git a/Adafruit_MAX31865.cpp b/Adafruit_MAX31865.cpp
index 30b2b05..6067939 100644
--- a/Adafruit_MAX31865.cpp
+++ b/Adafruit_MAX31865.cpp
@@ -103,6 +103,25 @@ uint8_t Adafruit_MAX31865::readFault(void) {
   return readRegister8(MAX31856_FAULTSTAT_REG);
 }
 
+/**************************************************************************/
+/*!
+    @brief Read the raw 8-bit FAULTSTAT register
+    @param b If true perform a automatic fault-detection cycle
+    @return The raw unsigned 8-bit FAULT status register
+*/
+/**************************************************************************/
+uint8_t Adafruit_MAX31865::readFault(boolean b) {
+  uint8_t t = readRegister8(MAX31856_CONFIG_REG);
+  if (b) {
+    t |= MAX31856_CONFIG_FAULTDETCYCLE;  // trigger automatic fault-detection cycle
+    writeRegister8(MAX31856_CONFIG_REG, t);
+	delay(5);  // wait for 5ms
+  }
+  
+  return readRegister8(MAX31856_FAULTSTAT_REG);
+}
+
+
 /**************************************************************************/
 /*!
     @brief Clear all faults in FAULTSTAT
diff --git a/Adafruit_MAX31865.h b/Adafruit_MAX31865.h
index e30bed8..e9cfd79 100644
--- a/Adafruit_MAX31865.h
+++ b/Adafruit_MAX31865.h
@@ -24,6 +24,7 @@
 #define MAX31856_CONFIG_1SHOT 0x20
 #define MAX31856_CONFIG_3WIRE 0x10
 #define MAX31856_CONFIG_24WIRE 0x00
+#define MAX31865_CONFIG_FAULTDETCYCLE  0x84
 #define MAX31856_CONFIG_FAULTSTAT 0x02
 #define MAX31856_CONFIG_FILT50HZ 0x01
 #define MAX31856_CONFIG_FILT60HZ 0x00
@@ -68,6 +69,7 @@ class Adafruit_MAX31865 {
   bool begin(max31865_numwires_t x = MAX31865_2WIRE);
 
   uint8_t readFault(void);
+  uint8_t readFault(boolean b);
   void clearFault(void);
   uint16_t readRTD();