SAMD20: Fix some confusion what which pins are on which connectors

3 files changed, 29 insertions, 11 deletions

diff --git a/nuttx/configs/samd20-xplained/Kconfig b/nuttx/configs/samd20-xplained/Kconfig
index a5273229e..6e3bbbd0e 100644
--- a/nuttx/configs/samd20-xplained/Kconfig
+++ b/nuttx/configs/samd20-xplained/Kconfig
@@ -63,11 +63,18 @@ config SAMD20_XPLAINED_USART4_EXT1
 		Select this option if the serial console is on SERCOM4 connected via
 		EXT1.  The RX will be on PB9 and TX signal will be on PB8.
 
+config SAMD20_XPLAINED_USART4_EXT2
+	bool "EXT2"
+	depends on !SAMD20_XPLAINED_OLED1MODULE_EXT2 && !SAMD20_XPLAINED_IOMODULE_EXT2
+	---help---
+		Select this option if the serial console is on SERCOM4 connected via
+		EXT2.  The RX will be on PB13 and TX signal will be on PB12.
+
 config SAMD20_XPLAINED_USART4_EXT3
 	bool "EXT3"
 	---help---
 		Select this option if the serial console is on SERCOM4 connect via
-		EXT3.  The RX will be on PB13 and TX signal will be on PB12.
+		EXT3.  The RX will be on PB11 and TX signal will be on PB10.
 
 endchoice
 endif
diff --git a/nuttx/configs/samd20-xplained/README.txt b/nuttx/configs/samd20-xplained/README.txt
index c968c214f..86e7966da 100644
--- a/nuttx/configs/samd20-xplained/README.txt
+++ b/nuttx/configs/samd20-xplained/README.txt
@@ -403,18 +403,23 @@ Serial Consoles
   SERCOM4
   ------
 
-  SERCOM4 is available on connectors EXT1 and EXT3
+  SERCOM4 is available on connectors EXT1, EXT2, and EXT3, but using
+  different PORT pins:
 
-    PIN   EXT1 EXT3 GPIO Function
-    ----  ---- ---- ------------------
-     13   PB09 PB13 SERCOM4 / USART RX
-     14   PB08 PB12 SERCOM4 / USART TX
-     19   19        GND
-     20   20        VCC
+    PIN   EXT1 EXT2 EXT3 GPIO Function
+    ----  ---- ---- ---- ------------------
+     13   PB09 PB13 PB11 SERCOM4 / USART RX
+     14   PB08 PB12 PB12 SERCOM4 / USART TX
+     19   GND  GND  GND  N/A
+     20   VCC  VCC  VCC  N/A
+
+  There are options available in the NuttX configuration to select which
+  connector SERCOM4 is on:  SAMD20_XPLAINED_USART4_EXTn, where n=1, 2, or 3.
 
   If you have a TTL to RS-232 converter then this is the most convenient
-  serial console to use.  It is the default in all of these configurations.
-  An option is to use the virtual COM port.
+  serial console to use (because you don't lose the console device each time
+  you lose the USB connection).  It is the default in all of these
+  configurations.  An option is to use the virtual COM port.
 
   Virtual COM Port
   ----------------
diff --git a/nuttx/configs/samd20-xplained/include/board.h b/nuttx/configs/samd20-xplained/include/board.h
index 216e38c0b..c7956e8ba 100644
--- a/nuttx/configs/samd20-xplained/include/board.h
+++ b/nuttx/configs/samd20-xplained/include/board.h
@@ -372,12 +372,18 @@
 #  define BOARD_SERCOM4_PINMAP_PAD1  PORT_SERCOM4_PAD1_3
 #  define BOARD_SERCOM4_PINMAP_PAD2  0
 #  define BOARD_SERCOM4_PINMAP_PAD3  0
-#else /* if defined(CONFIG_SAMD20_XPLAINED_USART4_EXT3) */
+#elif defined(CONFIG_SAMD20_XPLAINED_USART4_EXT2)
 #  define BOARD_SERCOM4_MUXCONFIG    (USART_CTRLA_RXPAD1 | USART_CTRLA_TXPAD0)
 #  define BOARD_SERCOM4_PINMAP_PAD0  PORT_SERCOM4_PAD0_1
 #  define BOARD_SERCOM4_PINMAP_PAD1  PORT_SERCOM4_PAD1_1
 #  define BOARD_SERCOM4_PINMAP_PAD2  0
 #  define BOARD_SERCOM4_PINMAP_PAD3  0
+#else /* if defined(CONFIG_SAMD20_XPLAINED_USART4_EXT3) */
+#  define BOARD_SERCOM4_MUXCONFIG    (USART_CTRLA_RXPAD3 | USART_CTRLA_TXPAD2)
+#  define BOARD_SERCOM4_PINMAP_PAD0  0
+#  define BOARD_SERCOM4_PINMAP_PAD1  0
+#  define BOARD_SERCOM4_PINMAP_PAD2  PORT_SERCOM4_PAD2_3
+#  define BOARD_SERCOM4_PINMAP_PAD3  PORT_SERCOM4_PAD3_3
 #endif
 
 #define BOARD_SERCOM4_FREQUENCY      BOARD_GCLK0_FREQUENCY