From 48de083c0d3d31d08b056ca1167e8a8e66948146 Mon Sep 17 00:00:00 2001
From: vk3il <david@vk3il.net>
Date: Sun, 7 May 2017 21:49:16 +1000
Subject: [PATCH 1/7] Added AUTO_BAND feature

Added AUTO_BAND feature and extended S_ERROR to include an error number
for debugging purposes.
---
 SODA_POP/SODA_POP.h   |   5 +++
 SODA_POP/SODA_POP.ino | 102 +++++++++++++++++++++++++++++++++++++++---
 SODA_POP/buttons.ino  |   2 +-
 SODA_POP/display.ino  |   4 +-
 SODA_POP/settings.h   |   3 ++
 5 files changed, 108 insertions(+), 8 deletions(-)

diff --git a/SODA_POP/SODA_POP.h b/SODA_POP/SODA_POP.h
index 03beeb5..4cb68b2 100644
--- a/SODA_POP/SODA_POP.h
+++ b/SODA_POP/SODA_POP.h
@@ -87,6 +87,11 @@ byte memory_index_character;
 #define EEPROM_CW_SPEED  7 // 1 byte
 #endif
 
+#ifdef AUTO_BAND 
+#define PCA9536_BUS_ADDR 0x41	// I2C address for PCA9536
+#undef OPT_BAND_SELECT
+#endif
+
 #endif
 
 // vim: tabstop=2 shiftwidth=2 expandtab:
diff --git a/SODA_POP/SODA_POP.ino b/SODA_POP/SODA_POP.ino
index 60facce..ac2f4a1 100644
--- a/SODA_POP/SODA_POP.ino
+++ b/SODA_POP/SODA_POP.ino
@@ -70,6 +70,7 @@ Si5351 si5351;
 #define IF_DEFAULT 491480000
 
 byte memory_pointer;
+byte errno;           // Global error number for S_ERROR
 
 const int MUTE = A3;
 const int TXEN = 13; // production A0
@@ -142,11 +143,18 @@ void setup()
   TIMSK1 |= 1 << OCIE1A;
   interrupts();
 
+#ifdef AUTO_BAND
+  if (EEPROM.read(6) == 0xff)                  // EEPROM 6 becomes a "not calibrated" flag
+    state.state = S_CALIBRATION_CORRECTION;    // Not sure that this will have the desired effect as
+                                               // state.state is set to S_DEFAULT a few lines below...
+  read_module_band();
+#else
   state.band = (enum band) EEPROM.read(6); // check for operating band
   if (state.band == BAND_UNKNOWN) {
     state.band = (enum band) 0;
     state.state = S_CALIBRATION_CORRECTION;
   }
+#endif
 
   fetch_calibration_data(); //load calibration data
   si5351.set_correction(cal_value); //correct the clock chip error
@@ -194,7 +202,7 @@ void loop()
     case S_CALIBRATION_PEAK_RX:     loop_calibration_peak_rx(); break;
     case S_ERROR:                   loop_error(); break;
     default:
-      error();
+      error(1);
       break;
   }
 
@@ -237,6 +245,10 @@ void loop_default()
     state.idle_for = DISABLE_DISPLAY_AFTER - 500;
 #endif
 
+#ifdef AUTO_BAND
+  if (tcount mod 5000 == 1) read_module_band();   // Check the band module for changes every 5s
+#endif
+
   if (key_active()) {
     state.state = S_KEYING;
   // Tuning with the rotary encoder
@@ -795,8 +807,12 @@ void loop_calibration_peak_if()
     EEPROM.write(EEPROM_IF_FREQ + 1, state.op_freq >> 8);
     EEPROM.write(EEPROM_IF_FREQ + 2, state.op_freq >> 16);
     EEPROM.write(EEPROM_IF_FREQ + 3, state.op_freq >> 24);
-
+ #ifdef AUTO_BAND
+    EEPROM.write(6,0);    // Reset the "not calibrated" flag now that we've written the cal values
+    state.state = S_CALIBRATION_PEAK_RX;
+#else
     state.state = S_CALIBRATION_CHANGE_BAND;
+#endif
     invalidate_frequencies();
     invalidate_display();
 
@@ -865,7 +881,7 @@ void key_handle_end()
     state.state = S_DEFAULT;
   } else if (state.state == S_MEM_ENTER) {
     if (memory_pointer == MEMORY_LENGTH) {
-      error();
+      error(2);
       return;
     }
     buffer[memory_pointer++] = morse_char;
@@ -1090,10 +1106,86 @@ void ee_erase()
  * Enter the error state. This error is non-recoverable and should only be used
  * in very rare cases.
  */
-void error()
+void error(int er)
 {
+  errno = er;
   state.state = S_ERROR;
-  invalidate_display();
 }
 
+#ifdef AUTO_BAND
+/*
+ * Read the input latch of the PCA9536 and return a 4-bit value
+ * If the band module can't be read or the value is out of range, display an error and wait for a valid band module
+ */
+ 
+byte PCA9536_read()
+{
+  byte reg_val;
+	byte err = FALSE;			// Flag for error reading band value
+	 
+	while (!err) {
+	  Wire.beginTransmission(PCA9536_BUS_ADDR);
+	  Wire.write(0);                           // We read only from register 0, the input latch
+	  Wire.endTransmission();
+	  Wire.requestFrom(PCA9536_BUS_ADDR, 1);
+	  if (Wire.available() != 1)	{  		// Unable to read the band module ID (most 
+                                      // likely it's not plugged in properly, or being changed!)
+      digit4 = LED_N_6;
+      digit3 = LED_n;
+	    digit2 = LED_E;
+		  digit1 = LED_r;
+		  err = TRUE;
+		  delay(500);
+	  } else {
+  	  reg_val = Wire.read() & 0x0f;
+	    if( reg_val < 2 || reg_val > 11) {	  // Module has an un-supported configuration
+        digit4 = LED_N_6;
+        digit3 = LED_n;
+	      digit2 = LED_E;
+		    digit1 = LED_r;
+		    err = TRUE;
+		    delay(500);
+	    } else err = FALSE;
+	  }
+	}
+ 	return reg_val;
+}
+
+/*
+ * Check if the band module has changed and if it has, reset bandlimits and operating frequency
+ */
+ 
+void read_module_band()
+{    
+     enum band new_band;
+	 
+     switch (PCA9536_read()) {                // Map returned value to current band table range
+       case 2:   new_band = BAND_160; break;
+       case 3:   new_band = BAND_80;  break;
+#ifdef BAND_60
+       case 4:   new_band = BAND_60;  break;
+#endif
+       case 5:   new_band = BAND_40;  break;
+       case 6:   new_band = BAND_30;  break;
+       case 7:   new_band = BAND_20;  break;
+       case 8:   new_band = BAND_17;  break;
+       case 9:   new_band = BAND_15;  break;
+       case 10:  new_band = BAND_12;  break;
+       case 11:  new_band = BAND_10;  break;
+       default:  new_band = BAND_UNKNOWN; error(3); break;
+     }
+     
+     if (new_band != state.band) {
+		   digitalWrite(MUTE, LOW);	 // Make sure we are in receieve mode
+		   state.band = new_band;
+       digit4 = LED_N_6;
+       digit3 = LED_n;
+       setup_band();             // Set the band limits and default 
+                                 // operating frequency for the selected band
+		   invalidate_display();
+       delay(2000);              // Allow time to view the band on the display
+     }
+}
+
+#endif
 // vim: tabstop=2 shiftwidth=2 expandtab:
diff --git a/SODA_POP/buttons.ino b/SODA_POP/buttons.ino
index 1d0fced..b486b38 100644
--- a/SODA_POP/buttons.ino
+++ b/SODA_POP/buttons.ino
@@ -150,7 +150,7 @@ unsigned int time_encoder_button()
 }
 
 /**
- * Debounche the keyer button.
+ * Debounce the keyer button.
  */
 void debounce_keyer()
 {
diff --git a/SODA_POP/display.ino b/SODA_POP/display.ino
index ad56ec1..a2c82eb 100644
--- a/SODA_POP/display.ino
+++ b/SODA_POP/display.ino
@@ -165,8 +165,8 @@ void invalidate_display()
     case S_ERROR:
       state.display.digits[3] = LED_E;
       state.display.digits[2] = LED_r;
-      state.display.digits[1] = LED_r;
-      state.display.digits[0] = 0x00;
+      state.display.digits[1] = 0x00;
+      state.display.digits[0] = LED_DIGITS[errno];
       state.display.dots = 0x2;
       break;
   }
diff --git a/SODA_POP/settings.h b/SODA_POP/settings.h
index 7afd8b3..d69ec36 100644
--- a/SODA_POP/settings.h
+++ b/SODA_POP/settings.h
@@ -37,6 +37,9 @@
 /* Band selection by pressing RIT for 2s */
 #define OPT_BAND_SELECT
 
+/* Autoband selection based on plugged in module - enabled by PCA9536 PIO on board module */
+#define AUTO_BAND
+
 /* Erase EEPROM by pressing RIT for 8s */
 #define OPT_ERASE_EEPROM
 

From 3b0c6e74da20a28d233984be32b12342f24a341e Mon Sep 17 00:00:00 2001
From: vk3il <david@vk3il.net>
Date: Sun, 7 May 2017 22:51:22 +1000
Subject: [PATCH 2/7] Syntax error correction

Syntax error corections
---
 SODA_POP/SODA_POP.h   |  3 +++
 SODA_POP/SODA_POP.ino | 37 +++++++++++++++++--------------------
 SODA_POP/settings.h   |  4 ++--
 3 files changed, 22 insertions(+), 22 deletions(-)

diff --git a/SODA_POP/SODA_POP.h b/SODA_POP/SODA_POP.h
index 4cb68b2..5d9dfe6 100644
--- a/SODA_POP/SODA_POP.h
+++ b/SODA_POP/SODA_POP.h
@@ -92,6 +92,9 @@ byte memory_index_character;
 #undef OPT_BAND_SELECT
 #endif
 
+#define TRUE   1
+#define FALSE  0
+
 #endif
 
 // vim: tabstop=2 shiftwidth=2 expandtab:
diff --git a/SODA_POP/SODA_POP.ino b/SODA_POP/SODA_POP.ino
index ac2f4a1..3a656ed 100644
--- a/SODA_POP/SODA_POP.ino
+++ b/SODA_POP/SODA_POP.ino
@@ -246,7 +246,7 @@ void loop_default()
 #endif
 
 #ifdef AUTO_BAND
-  if (tcount mod 5000 == 1) read_module_band();   // Check the band module for changes every 5s
+  if (tcount % 5000 == 1) read_module_band();   // Check the band module for changes every 5s
 #endif
 
   if (key_active()) {
@@ -1128,24 +1128,22 @@ byte PCA9536_read()
 	  Wire.write(0);                           // We read only from register 0, the input latch
 	  Wire.endTransmission();
 	  Wire.requestFrom(PCA9536_BUS_ADDR, 1);
-	  if (Wire.available() != 1)	{  		// Unable to read the band module ID (most 
-                                      // likely it's not plugged in properly, or being changed!)
-      digit4 = LED_N_6;
-      digit3 = LED_n;
-	    digit2 = LED_E;
-		  digit1 = LED_r;
+    err = FALSE;
+	  if (Wire.available() != 1)  		// Unable to read the band module ID (most 
+                                    // likely it's not plugged in properly, or being changed!)
 		  err = TRUE;
-		  delay(500);
-	  } else {
+	  else {
   	  reg_val = Wire.read() & 0x0f;
-	    if( reg_val < 2 || reg_val > 11) {	  // Module has an un-supported configuration
-        digit4 = LED_N_6;
-        digit3 = LED_n;
-	      digit2 = LED_E;
-		    digit1 = LED_r;
-		    err = TRUE;
-		    delay(500);
-	    } else err = FALSE;
+	    if( reg_val < 2 || reg_val > 11)	  // Module has an un-supported configuration
+        err = TRUE;
+	  }
+    if (err) {
+      state.display.digits[3] = LED_N_6;
+      state.display.digits[2] = LED_n;
+      state.display.digits[1] = LED_E;
+      state.display.digits[0] = LED_r;
+      state.display.dots = 0x0;
+      delay(500);
 	  }
 	}
  	return reg_val;
@@ -1178,12 +1176,11 @@ void read_module_band()
      if (new_band != state.band) {
 		   digitalWrite(MUTE, LOW);	 // Make sure we are in receieve mode
 		   state.band = new_band;
-       digit4 = LED_N_6;
-       digit3 = LED_n;
        setup_band();             // Set the band limits and default 
                                  // operating frequency for the selected band
-		   invalidate_display();
+       display_band();
        delay(2000);              // Allow time to view the band on the display
+       invalidate_display();
      }
 }
 
diff --git a/SODA_POP/settings.h b/SODA_POP/settings.h
index d69ec36..7f8c5f1 100644
--- a/SODA_POP/settings.h
+++ b/SODA_POP/settings.h
@@ -26,7 +26,7 @@
  * #define DEFAULT_OP_FREQ_20 1405500000
  * ... setting the default frequency to 14.055 MHz on 20m.
  */
-#define PLAN_IARU2
+#define PLAN_IARU3
 
 /* Custom default operating frequencies, per band, in mHz.
  * See bands.h for defaults */
@@ -50,7 +50,7 @@
 #define OPT_DFE
 
 /* Disable display when idle */
-#define OPT_DISABLE_DISPLAY
+//#define OPT_DISABLE_DISPLAY
 #define DISABLE_DISPLAY_AFTER 2500 /* Time to disable display after, in ms */
 
 /* More message memories. Select using the rotary encoder. */

From 5009fba8900ddb31cc98cf65a5793f1f561a170c Mon Sep 17 00:00:00 2001
From: vk3il <david@vk3il.net>
Date: Mon, 8 May 2017 11:59:34 +1000
Subject: [PATCH 3/7] Added debug code to PCA9536_read()

Need to find out why PCA9536 isn't responding.
---
 SODA_POP/SODA_POP.ino | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/SODA_POP/SODA_POP.ino b/SODA_POP/SODA_POP.ino
index 3a656ed..b27ead2 100644
--- a/SODA_POP/SODA_POP.ino
+++ b/SODA_POP/SODA_POP.ino
@@ -1126,9 +1126,10 @@ byte PCA9536_read()
 	while (!err) {
 	  Wire.beginTransmission(PCA9536_BUS_ADDR);
 	  Wire.write(0);                           // We read only from register 0, the input latch
-	  Wire.endTransmission();
+	  err = Wire.endTransmission();
+	  if (err) error(err);			 // if transmit failed, stop for debugging
 	  Wire.requestFrom(PCA9536_BUS_ADDR, 1);
-    err = FALSE;
+          err = FALSE;
 	  if (Wire.available() != 1)  		// Unable to read the band module ID (most 
                                     // likely it's not plugged in properly, or being changed!)
 		  err = TRUE;

From 7404de27aac951acff2aa0a471307e8f5408f76b Mon Sep 17 00:00:00 2001
From: vk3il <david@vk3il.net>
Date: Mon, 8 May 2017 12:18:07 +1000
Subject: [PATCH 4/7] Debugging

Added repeated start condition to I2C transmission
---
 SODA_POP/SODA_POP.ino | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/SODA_POP/SODA_POP.ino b/SODA_POP/SODA_POP.ino
index b27ead2..6f29ab9 100644
--- a/SODA_POP/SODA_POP.ino
+++ b/SODA_POP/SODA_POP.ino
@@ -1126,7 +1126,7 @@ byte PCA9536_read()
 	while (!err) {
 	  Wire.beginTransmission(PCA9536_BUS_ADDR);
 	  Wire.write(0);                           // We read only from register 0, the input latch
-	  err = Wire.endTransmission();
+	  err = Wire.endTransmission(false);	  // Transmit repeated start rather than stop at end of transmission
 	  if (err) error(err);			 // if transmit failed, stop for debugging
 	  Wire.requestFrom(PCA9536_BUS_ADDR, 1);
           err = FALSE;

From de6aae9567564955eeb64d97396ccb574585e41a Mon Sep 17 00:00:00 2001
From: vk3il <david@vk3il.net>
Date: Tue, 9 May 2017 22:49:40 +1000
Subject: [PATCH 5/7] Debugging

Ironed out bugs in I2C PIO code - now appears to be working
---
 SODA_POP/SODA_POP.ino | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/SODA_POP/SODA_POP.ino b/SODA_POP/SODA_POP.ino
index 6f29ab9..253acac 100644
--- a/SODA_POP/SODA_POP.ino
+++ b/SODA_POP/SODA_POP.ino
@@ -1121,15 +1121,14 @@ void error(int er)
 byte PCA9536_read()
 {
   byte reg_val;
-	byte err = FALSE;			// Flag for error reading band value
+	byte err = TRUE;			// Flag for error reading band value
 	 
-	while (!err) {
+	while (err) {
 	  Wire.beginTransmission(PCA9536_BUS_ADDR);
-	  Wire.write(0);                           // We read only from register 0, the input latch
-	  err = Wire.endTransmission(false);	  // Transmit repeated start rather than stop at end of transmission
-	  if (err) error(err);			 // if transmit failed, stop for debugging
+	  Wire.write(byte(0x00));                 // We read only from register 0, the input latch
+	  Wire.endTransmission(false);	  // Transmit repeated start rather than stop at end of transmission
 	  Wire.requestFrom(PCA9536_BUS_ADDR, 1);
-          err = FALSE;
+    err = FALSE;
 	  if (Wire.available() != 1)  		// Unable to read the band module ID (most 
                                     // likely it's not plugged in properly, or being changed!)
 		  err = TRUE;
@@ -1147,6 +1146,7 @@ byte PCA9536_read()
       delay(500);
 	  }
 	}
+  invalidate_display();
  	return reg_val;
 }
 

From 311fd653e869c5afd354ee0ac2dcc8e84c7db089 Mon Sep 17 00:00:00 2001
From: Camil Staps <info@camilstaps.nl>
Date: Tue, 16 May 2017 15:06:28 +0000
Subject: [PATCH 6/7] Preparing #22 for merging. Sensible defaults and code
 style.

---
 SODA_POP/SODA_POP.h   |  5 +--
 SODA_POP/SODA_POP.ino | 78 +++++++++++++++++++++----------------------
 SODA_POP/display.ino  |  4 +--
 SODA_POP/settings.h   |  7 ++--
 4 files changed, 45 insertions(+), 49 deletions(-)

diff --git a/SODA_POP/SODA_POP.h b/SODA_POP/SODA_POP.h
index 5d9dfe6..85c251f 100644
--- a/SODA_POP/SODA_POP.h
+++ b/SODA_POP/SODA_POP.h
@@ -87,14 +87,11 @@ byte memory_index_character;
 #define EEPROM_CW_SPEED  7 // 1 byte
 #endif
 
-#ifdef AUTO_BAND 
+#ifdef OPT_AUTO_BAND
 #define PCA9536_BUS_ADDR 0x41	// I2C address for PCA9536
 #undef OPT_BAND_SELECT
 #endif
 
-#define TRUE   1
-#define FALSE  0
-
 #endif
 
 // vim: tabstop=2 shiftwidth=2 expandtab:
diff --git a/SODA_POP/SODA_POP.ino b/SODA_POP/SODA_POP.ino
index 253acac..4d9d098 100644
--- a/SODA_POP/SODA_POP.ino
+++ b/SODA_POP/SODA_POP.ino
@@ -143,16 +143,16 @@ void setup()
   TIMSK1 |= 1 << OCIE1A;
   interrupts();
 
-#ifdef AUTO_BAND
-  if (EEPROM.read(6) == 0xff)                  // EEPROM 6 becomes a "not calibrated" flag
-    state.state = S_CALIBRATION_CORRECTION;    // Not sure that this will have the desired effect as
-                                               // state.state is set to S_DEFAULT a few lines below...
+#ifdef OPT_AUTO_BAND
+  state.state = EEPROM.read(6) == 0xff ? S_CALIBRATION_CORRECTION : S_DEFAULT;
   read_module_band();
 #else
   state.band = (enum band) EEPROM.read(6); // check for operating band
   if (state.band == BAND_UNKNOWN) {
     state.band = (enum band) 0;
     state.state = S_CALIBRATION_CORRECTION;
+  } else {
+    state.state = S_DEFAULT;
   }
 #endif
 
@@ -163,7 +163,6 @@ void setup()
   invalidate_display();
   delay(1000);
 
-  state.state = S_DEFAULT;
   invalidate_display();
   digitalWrite(MUTE, LOW);
 
@@ -245,8 +244,9 @@ void loop_default()
     state.idle_for = DISABLE_DISPLAY_AFTER - 500;
 #endif
 
-#ifdef AUTO_BAND
-  if (tcount % 5000 == 1) read_module_band();   // Check the band module for changes every 5s
+#ifdef OPT_AUTO_BAND
+  if (tcount % 5000 == 0) // Check the band module for changes every 5s
+    read_module_band();
 #endif
 
   if (key_active()) {
@@ -807,8 +807,8 @@ void loop_calibration_peak_if()
     EEPROM.write(EEPROM_IF_FREQ + 1, state.op_freq >> 8);
     EEPROM.write(EEPROM_IF_FREQ + 2, state.op_freq >> 16);
     EEPROM.write(EEPROM_IF_FREQ + 3, state.op_freq >> 24);
- #ifdef AUTO_BAND
-    EEPROM.write(6,0);    // Reset the "not calibrated" flag now that we've written the cal values
+ #ifdef OPT_AUTO_BAND
+    EEPROM.write(6, 0); // Reset the "not calibrated" flag now that we've written the cal values
     state.state = S_CALIBRATION_PEAK_RX;
 #else
     state.state = S_CALIBRATION_CHANGE_BAND;
@@ -1106,37 +1106,36 @@ void ee_erase()
  * Enter the error state. This error is non-recoverable and should only be used
  * in very rare cases.
  */
-void error(int er)
+void error(byte er)
 {
   errno = er;
   state.state = S_ERROR;
 }
 
-#ifdef AUTO_BAND
+#ifdef OPT_AUTO_BAND
 /*
  * Read the input latch of the PCA9536 and return a 4-bit value
  * If the band module can't be read or the value is out of range, display an error and wait for a valid band module
  */
- 
 byte PCA9536_read()
 {
   byte reg_val;
-	byte err = TRUE;			// Flag for error reading band value
-	 
-	while (err) {
-	  Wire.beginTransmission(PCA9536_BUS_ADDR);
-	  Wire.write(byte(0x00));                 // We read only from register 0, the input latch
-	  Wire.endTransmission(false);	  // Transmit repeated start rather than stop at end of transmission
-	  Wire.requestFrom(PCA9536_BUS_ADDR, 1);
-    err = FALSE;
-	  if (Wire.available() != 1)  		// Unable to read the band module ID (most 
-                                    // likely it's not plugged in properly, or being changed!)
-		  err = TRUE;
-	  else {
-  	  reg_val = Wire.read() & 0x0f;
-	    if( reg_val < 2 || reg_val > 11)	  // Module has an un-supported configuration
-        err = TRUE;
-	  }
+  boolean err = true; // Flag for error reading band value
+
+  while (err) {
+    Wire.beginTransmission(PCA9536_BUS_ADDR);
+    Wire.write(byte(0x00));       // We read only from register 0, the input latch
+    Wire.endTransmission(false);  // Transmit repeated start rather than stop at end of transmission
+    Wire.requestFrom(PCA9536_BUS_ADDR, 1);
+    err = false;
+    if (Wire.available() != 1)    // Unable to read the band module ID (most
+                                  // likely it's not plugged in properly, or being changed!)
+      err = true;
+    else {
+      reg_val = Wire.read() & 0x0f;
+      if(reg_val < 2 || reg_val > 11) // Module has an un-supported configuration
+        err = true;
+    }
     if (err) {
       state.display.digits[3] = LED_N_6;
       state.display.digits[2] = LED_n;
@@ -1144,21 +1143,20 @@ byte PCA9536_read()
       state.display.digits[0] = LED_r;
       state.display.dots = 0x0;
       delay(500);
-	  }
-	}
+    }
+  }
   invalidate_display();
- 	return reg_val;
+  return reg_val;
 }
 
 /*
  * Check if the band module has changed and if it has, reset bandlimits and operating frequency
  */
- 
 void read_module_band()
-{    
+{
      enum band new_band;
-	 
-     switch (PCA9536_read()) {                // Map returned value to current band table range
+
+     switch (PCA9536_read()) { // Map returned value to current band table range
        case 2:   new_band = BAND_160; break;
        case 3:   new_band = BAND_80;  break;
 #ifdef BAND_60
@@ -1173,17 +1171,17 @@ void read_module_band()
        case 11:  new_band = BAND_10;  break;
        default:  new_band = BAND_UNKNOWN; error(3); break;
      }
-     
+
      if (new_band != state.band) {
-		   digitalWrite(MUTE, LOW);	 // Make sure we are in receieve mode
-		   state.band = new_band;
-       setup_band();             // Set the band limits and default 
+       digitalWrite(MUTE, LOW);  // Make sure we are in receieve mode
+       state.band = new_band;
+       setup_band();             // Set the band limits and default
                                  // operating frequency for the selected band
        display_band();
        delay(2000);              // Allow time to view the band on the display
        invalidate_display();
      }
 }
-
 #endif
+
 // vim: tabstop=2 shiftwidth=2 expandtab:
diff --git a/SODA_POP/display.ino b/SODA_POP/display.ino
index a2c82eb..249f013 100644
--- a/SODA_POP/display.ino
+++ b/SODA_POP/display.ino
@@ -165,8 +165,8 @@ void invalidate_display()
     case S_ERROR:
       state.display.digits[3] = LED_E;
       state.display.digits[2] = LED_r;
-      state.display.digits[1] = 0x00;
-      state.display.digits[0] = LED_DIGITS[errno];
+      state.display.digits[0] = LED_DIGITS[errno / 10];
+      state.display.digits[0] = LED_DIGITS[errno % 10];
       state.display.dots = 0x2;
       break;
   }
diff --git a/SODA_POP/settings.h b/SODA_POP/settings.h
index 7f8c5f1..8ab9125 100644
--- a/SODA_POP/settings.h
+++ b/SODA_POP/settings.h
@@ -22,11 +22,12 @@
  * - PLAN_IARU1
  * - PLAN_IARU2
  * - PLAN_IARU3
+ * - PLAN_VK
  * It is possible to override the default operating frequency using:
  * #define DEFAULT_OP_FREQ_20 1405500000
  * ... setting the default frequency to 14.055 MHz on 20m.
  */
-#define PLAN_IARU3
+#define PLAN_IARU2
 
 /* Custom default operating frequencies, per band, in mHz.
  * See bands.h for defaults */
@@ -37,8 +38,8 @@
 /* Band selection by pressing RIT for 2s */
 #define OPT_BAND_SELECT
 
-/* Autoband selection based on plugged in module - enabled by PCA9536 PIO on board module */
-#define AUTO_BAND
+/* Autoband selection based on plugged in module with PCA9536 PIO */
+//#define OPT_AUTO_BAND
 
 /* Erase EEPROM by pressing RIT for 8s */
 #define OPT_ERASE_EEPROM

From 1197d0a5b003262ef1cfc18a7e044beb3ac1b5be Mon Sep 17 00:00:00 2001
From: Camil Staps <info@camilstaps.nl>
Date: Tue, 16 May 2017 15:14:13 +0000
Subject: [PATCH 7/7] Prepare for merge

---
 README.md             |  3 +++
 SODA_POP/SODA_POP.ino | 16 ++++++----------
 2 files changed, 9 insertions(+), 10 deletions(-)

diff --git a/README.md b/README.md
index d7e7aa0..9fd56de 100644
--- a/README.md
+++ b/README.md
@@ -143,6 +143,7 @@ There are several features that can be added to the rig if you want to. This is
 done by adding and removing `#define` lines to `settings.h`.
 
 - `OPT_BAND_SELECT`: change the band by pressing RIT for 2s.
+- `OPT_AUTO_BAND`: auto-select bands using a PCA9536 PIO (thanks VK3IL).
 - `OPT_ERASE_EEPROM`: erase the EEPROM by holding RIT for 8s.
 - `OPT_STORE_CW_SPEED`: store the CW speed in EEPROM.
 - `OPT_DFE`: direct frequency entry by holding the encoder button for 1s.
@@ -208,6 +209,8 @@ Some images of the connections:
 
 ## Changelog
 
+- 2017-05-16:
+  - `OPT_AUTO_BAND` (PR [#22](/../../pull/22) by VK3IL)
 - 2017-05-04:
   - Beacon mode (issue [#6](/../../issues/6))
   - More logical UX for sending and storing memories, using RIT to cancel
diff --git a/SODA_POP/SODA_POP.ino b/SODA_POP/SODA_POP.ino
index 4d9d098..9c519a1 100644
--- a/SODA_POP/SODA_POP.ino
+++ b/SODA_POP/SODA_POP.ino
@@ -70,7 +70,7 @@ Si5351 si5351;
 #define IF_DEFAULT 491480000
 
 byte memory_pointer;
-byte errno;           // Global error number for S_ERROR
+byte errno; // Global error number for S_ERROR
 
 const int MUTE = A3;
 const int TXEN = 13; // production A0
@@ -1119,20 +1119,16 @@ void error(byte er)
  */
 byte PCA9536_read()
 {
-  byte reg_val;
-  boolean err = true; // Flag for error reading band value
-
-  while (err) {
+  for (boolean err = true; err; err = false) {
     Wire.beginTransmission(PCA9536_BUS_ADDR);
     Wire.write(byte(0x00));       // We read only from register 0, the input latch
     Wire.endTransmission(false);  // Transmit repeated start rather than stop at end of transmission
     Wire.requestFrom(PCA9536_BUS_ADDR, 1);
-    err = false;
-    if (Wire.available() != 1)    // Unable to read the band module ID (most
+    if (Wire.available() != 1) {  // Unable to read the band module ID (most
                                   // likely it's not plugged in properly, or being changed!)
       err = true;
-    else {
-      reg_val = Wire.read() & 0x0f;
+    } else {
+      byte reg_val = Wire.read() & 0x0f;
       if(reg_val < 2 || reg_val > 11) // Module has an un-supported configuration
         err = true;
     }
@@ -1173,7 +1169,7 @@ void read_module_band()
      }
 
      if (new_band != state.band) {
-       digitalWrite(MUTE, LOW);  // Make sure we are in receieve mode
+       digitalWrite(MUTE, LOW);  // Make sure we are in receive mode
        state.band = new_band;
        setup_band();             // Set the band limits and default
                                  // operating frequency for the selected band