From 1dc0842557722c35ebf3652efe9ee862c1c0a857 Mon Sep 17 00:00:00 2001
From: AJ Christensen <aj@junglistheavy.industries>
Date: Mon, 25 Mar 2019 23:48:00 +1300
Subject: [PATCH] Revert "SmartAudio Lite compatibility: Send 0x00 bit(s)
 (always) even with Soft Serial."

---
 src/main/io/vtx_smartaudio.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/main/io/vtx_smartaudio.c b/src/main/io/vtx_smartaudio.c
index 08b0b3681..803801ab0 100644
--- a/src/main/io/vtx_smartaudio.c
+++ b/src/main/io/vtx_smartaudio.c
@@ -450,7 +450,14 @@ static void saReceiveFrame(uint8_t c)
 static void saSendFrame(uint8_t *buf, int len)
 {
     if (!IS_RC_MODE_ACTIVE(BOXVTXCONTROLDISABLE)) {
-        serialWrite(smartAudioSerialPort, 0x00); // Ensure line is low regardless of hardware pull-down capabilities.
+        switch (smartAudioSerialPort->identifier) {
+            case SERIAL_PORT_SOFTSERIAL1:
+            case SERIAL_PORT_SOFTSERIAL2:
+                break;
+            default:
+                serialWrite(smartAudioSerialPort, 0x00); // Generate 1st start bit
+                break;
+        }
 
         for (int i = 0 ; i < len ; i++) {
             serialWrite(smartAudioSerialPort, buf[i]);
@@ -461,7 +468,6 @@ static void saSendFrame(uint8_t *buf, int len)
         sa_outstanding = SA_CMD_NONE;
     }
 
-    serialWrite(smartAudioSerialPort, 0x00); // Pull the line low again after sending frame.
     sa_lastTransmissionMs = millis();
 }