From 149f5b034d3adb1c15d1628bdc3ebd315d01731e Mon Sep 17 00:00:00 2001
From: Mike Causer <mcauser@gmail.com>
Date: Fri, 14 Apr 2023 12:39:32 +1000
Subject: [PATCH] Rollback AU915 to FSB2 add DualPlan and AS923

---
 main/ttn.cpp   | 19 ++++++++++++++-----
 platformio.ini |  4 +++-
 2 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/main/ttn.cpp b/main/ttn.cpp
index b576f7c..2cb9732 100644
--- a/main/ttn.cpp
+++ b/main/ttn.cpp
@@ -325,14 +325,23 @@ void ttn_join(void) {
   // other regions, this will need to be changed.
   LMIC_selectSubBand(1);
 
+#elif defined(CFG_au915) && defined(CFG_au915_fsb6)
+
+  // AU915 FSB6
+  // CH 40-47 (923.2 - 924.6 MHz)
+  // Helium DualPlan was live in Australia 2022-11-17 to 2023-04-18
+  // DualPlan allowed AU915 devices to co-exist with AS923 by taking advantage
+  // of some AU915 FSB6 frequencies overlapping AS923 frequencies.
+  // If a device joined on the first two channels of FSB6, it was treated as
+  // an AS923 device. On the last 6 channels, an AU915 device.
+  LMIC_selectSubBand(5);
+
 #elif defined(CFG_au915)
 
-  // set sub band for AU915
-  // before 2022-11-17 Helium was using FSB2 CH 8-15 (916.8 - 918.2 MHz uplink)
+  // AU915 FSB2
+  // CH 8-15 (916.8 - 918.2 MHz uplink)
   // https://github.com/TheThingsNetwork/gateway-conf/blob/master/AU-global_conf.json
-  // LMIC_selectSubBand(1);
-  // after 2022-11-17 Helium switched to DualPlan using FSB6 CH 40-47 (923.2 - 924.6 MHz uplink)
-  LMIC_selectSubBand(5);
+  LMIC_selectSubBand(1);
 
 #endif
 
diff --git a/platformio.ini b/platformio.ini
index 244061d..9c106ba 100644
--- a/platformio.ini
+++ b/platformio.ini
@@ -21,6 +21,8 @@ build_flags = -Wall
 	-D CFG_us915=1
 ;	-D CFG_eu868=1
 ;	-D CFG_au915=1
+;	-D CFG_au915_fsb6=1
+;	-D CFG_as923=1
 	-D CFG_sx1276_radio=1
 	-D ARDUINO_LMIC_PROJECT_CONFIG_H_SUPPRESS
 	-D ARDUINO_TTGO_LoRa32_V1
@@ -40,5 +42,5 @@ monitor_speed = 115200
 
 [env:debug]
 debug_build_flags = 
-    -D DEBUG
+	-D DEBUG
 	-D LMIC_DEBUG_LEVEL=3