From 1f3925a46252a344789a832c6ff29626ae645796 Mon Sep 17 00:00:00 2001
From: Rob Riggs <rob@pangalactic.org>
Date: Mon, 25 Oct 2021 20:20:57 -0500
Subject: [PATCH] Fix M17 RX reverse polarity.

---
 TNC/KissHardware.cpp   |  6 +++---
 TNC/M17Demodulator.cpp | 10 ++++------
 2 files changed, 7 insertions(+), 9 deletions(-)

diff --git a/TNC/KissHardware.cpp b/TNC/KissHardware.cpp
index a0cc572..c224061 100644
--- a/TNC/KissHardware.cpp
+++ b/TNC/KissHardware.cpp
@@ -43,13 +43,13 @@ int powerOffViaUSB(void)
 namespace mobilinkd { namespace tnc { namespace kiss {
 
 #if defined(NUCLEOTNC)
-const char FIRMWARE_VERSION[] = "2.4.0";
+const char FIRMWARE_VERSION[] = "2.4.1";
 const char HARDWARE_VERSION[] = "Mobilinkd NucleoTNC";
 #elif defined(STM32L433xx)
-const char FIRMWARE_VERSION[] = "2.4.0";
+const char FIRMWARE_VERSION[] = "2.4.1";
 const char HARDWARE_VERSION[] = "Mobilinkd TNC3 2.1.1";
 #elif defined(STM32L4P5xx)
-const char FIRMWARE_VERSION[] = "2.4.0";
+const char FIRMWARE_VERSION[] = "2.4.1";
 const char HARDWARE_VERSION[] = "Mobilinkd TNC3+ Rev A";
 #endif
 Hardware& settings()
diff --git a/TNC/M17Demodulator.cpp b/TNC/M17Demodulator.cpp
index c60f86f..02d82a9 100644
--- a/TNC/M17Demodulator.cpp
+++ b/TNC/M17Demodulator.cpp
@@ -19,6 +19,8 @@ namespace mobilinkd { namespace tnc {
 //m17::Indicator dcd_indicator{GPIOA, GPIO_PIN_2};
 //m17::Indicator str_indicator{GPIOA, GPIO_PIN_7};
 
+static float scale = 1.f / 2560.f;
+
 void M17Demodulator::start()
 {
     SysClock72();
@@ -29,6 +31,7 @@ void M17Demodulator::start()
     demod_filter.init(m17::rrc_taps_f15);
     passall(kiss::settings().options & KISS_OPTION_PASSALL);
     polarity = kiss::settings().rx_rev_polarity() ? -1 : 1;
+    scale = 1.f / 2560.f * polarity;
     audio::virtual_ground = (VREF + 1) / 2;
 
     hadc1.Init.OversamplingMode = ENABLE;
@@ -57,7 +60,7 @@ void M17Demodulator::update_values(uint8_t index)
 {
     correlator.apply([this,index](float t){dev.sample(t);}, index);
     dev.update();
-    idev = dev.idev() * polarity;
+    idev = dev.idev();
     sync_sample_index = index;
 }
 
@@ -87,9 +90,6 @@ void M17Demodulator::dcd_off()
 
 void M17Demodulator::initialize(const q15_t* input)
 {
-
-    static constexpr float scale = 1.f / 2560.f;
-
     for (size_t i = 0; i != ADC_BLOCK_SIZE; i++) {
         demod_buffer[i] = float(input[i]) * scale;
     }
@@ -451,8 +451,6 @@ hdlc::IoFrame* M17Demodulator::operator()(const q15_t* input)
     // Do adc_micro_adjustment() here?
     // adc_micro_adjustment();
 
-    static constexpr float scale = 1.f / 2560.f;
-
     for (size_t i = 0; i != ADC_BLOCK_SIZE; i++) {
         demod_buffer[i] = float(input[i]) * scale;
     }