change autodection so only SW SPI needs pins listed in config.py

config.py

@@ -38,14 +38,16 @@ currency_type   = "$"   # Currency Symbol to show when calculating cost to run j
 #
 # - faster
 # - requires 3 specific GPIO pins be used on rpis
+# - no pins are listed in this config file 
 # 
 # Software SPI
 #
 # - slower (which will not matter for reading a thermocouple
 # - can use any GPIO pins
+# - pins must be specified in this config file
 
 #######################################
-# SPI pins if you choose hardware spi #
+# SPI pins if you choose Hardware SPI #
 #######################################
 # On the raspberry pi, you MUST use predefined
 # pins for HW SPI. In the case of the adafruit-31855, only 3 pins are used:
@@ -58,6 +60,8 @@ currency_type   = "$"   # Currency Symbol to show when calculating cost to run j
 # I chose gpio pin 5:
 #
 #    GPIO5    = BCM pin 5   = CS on the adafruit-31855
+#
+# Note that NO pins are configured in this file for hardware spi
 
 #######################################
 # SPI pins if you choose software spi #
@@ -66,12 +70,11 @@ currency_type   = "$"   # Currency Symbol to show when calculating cost to run j
 # You must connect clock, mosi, miso and cs each to a GPIO pin
 # and configure them below based on your connections.
 
-
 #######################################
 # SPI is Autoconfigured !!!
 #######################################
-# whether you choose HW or SW spi, it is autodetected. If you use the hw pins
+# whether you choose HW or SW spi, it is autodetected. If you list the PINs
-# HW spi is assumed.
+# below, software spi is assumed.
 
 #######################################
 # Output to control the relay
@@ -81,10 +84,10 @@ currency_type   = "$"   # Currency Symbol to show when calculating cost to run j
 
 try:
     import board
-    spi_sclk  = board.D11 #spi clock
+    spi_sclk  = board.D17 #spi clock
+    spi_miso  = board.D27  #spi Microcomputer In Serial Out
+    spi_cs    = board.D22  #spi Chip Select
     spi_mosi  = board.D10 #spi Microcomputer Out Serial In (not connected) 
-    spi_miso  = board.D9  #spi Microcomputer In Serial Out
-    spi_cs    = board.D5  #spi Chip Select
     gpio_heat = board.D23 #output that controls relay
 except (NotImplementedError,AttributeError):
     print("not running on blinka recognized board, probably a simulation")

lib/oven.py

@@ -121,26 +121,17 @@ class TempSensorReal(TempSensor):
         self.spi_setup()
         self.cs = digitalio.DigitalInOut(config.spi_cs)
 
-    def hw_spi(self):
-        import board
-        if(hasattr(board,'SCLK') and
-           hasattr(board,'MOSI') and 
-           hasattr(board,'MISO')):
-            if(board.SCLK == config.spi_sclk and
-               board.MOSI == config.spi_mosi and
-               board.MISO == config.spi_miso):
-               return board.SPI();
-        return None
-
     def spi_setup(self):
-        self.spi = self.hw_spi()
+        if(hasattr(config,'spi_sclk') and
-        if self.spi is None:
+           hasattr(config,'spi_mosi') and
+           hasattr(config,'spi_miso')):
             self.spi = bitbangio.SPI(config.spi_sclk, config.spi_mosi, config.spi_miso)
             log.info("Software SPI selected for reading thermocouple")
         else:
+            import board
+            self.spi = board.SPI();
             log.info("Hardware SPI selected for reading thermocouple")
 
-
     def get_temperature(self):
         '''read temp from tc and convert if needed'''
         try:

test-thermocouple.py

@@ -30,18 +30,19 @@ except NotImplementedError:
 ########################################################################
 
 spi = None
-if(hasattr(board,'SCLK') and
+if(hasattr(config,'spi_sclk') and
-    hasattr(board,'MOSI') and
+   hasattr(config,'spi_mosi') and
-    hasattr(board,'MISO')):
+   hasattr(config,'spi_miso')):
-    if(board.SCLK == config.spi_sclk and
-        board.MOSI == config.spi_mosi and
-        board.MISO == config.spi_miso):
-        spi = board.SPI();
-        print("Hardware SPI selected for reading thermocouple")
-
-if spi is None:
     spi = bitbangio.SPI(config.spi_sclk, config.spi_mosi, config.spi_miso)
     print("Software SPI selected for reading thermocouple")
+    print("SPI configured as:\n")
+    print("    config.spi_sclk = %s BCM pin" % (config.spi_sclk))
+    print("    config.spi_mosi = %s BCM pin" % (config.spi_mosi))
+    print("    config.spi_miso = %s BCM pin" % (config.spi_miso))
+    print("    config.spi_cs   = %s BCM pin\n" % (config.spi_cs))
+else:
+    spi = board.SPI();
+    print("Hardware SPI selected for reading thermocouple")
 
 cs = DigitalInOut(config.spi_cs)
 cs.switch_to_output(value=True)
@@ -57,11 +58,6 @@ if(config.max31856):
     print("thermocouple: adafruit max31856")
     sensor = adafruit_max31856.MAX31856(spi, cs)
 
-print("SPI configured as:\n")
-print("    config.spi_sclk = %s BCM pin" % (config.spi_sclk))
-print("    config.spi_mosi = %s BCM pin" % (config.spi_mosi))
-print("    config.spi_miso = %s BCM pin" % (config.spi_miso))
-print("    config.spi_cs   = %s BCM pin\n" % (config.spi_cs))
 print("Degrees displayed in %s\n" % (config.temp_scale))
 
 temp = 0