From 5daee639223cf0da0e994172c4f2a13d8309a3ed Mon Sep 17 00:00:00 2001
From: Bertrand Songis <bsongis@gmail.com>
Date: Fri, 8 Nov 2019 20:00:31 +0100
Subject: [PATCH] PMU flash issue on Horus

---
 radio/src/io/frsky_firmware_update.cpp       | 7 ++++++-
 radio/src/targets/horus/telemetry_driver.cpp | 6 ++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/radio/src/io/frsky_firmware_update.cpp b/radio/src/io/frsky_firmware_update.cpp
index d8a8933e9..c42a0d071 100644
--- a/radio/src/io/frsky_firmware_update.cpp
+++ b/radio/src/io/frsky_firmware_update.cpp
@@ -549,7 +549,7 @@ const char * FrskyChipFirmwareUpdate::waitAnswer(uint8_t & status)
   uint8_t buffer[12];
   for (uint8_t i = 0; i < sizeof(buffer); i++) {
     uint32_t retry = 0;
-    while(1) {
+    while (true) {
       if (telemetryGetByte(&buffer[i])) {
         if ((i == 0 && buffer[0] != 0x7F) ||
             (i == 1 && buffer[1] != 0xFE) ||
@@ -572,6 +572,10 @@ const char * FrskyChipFirmwareUpdate::waitAnswer(uint8_t & status)
 
 const char * FrskyChipFirmwareUpdate::startBootloader()
 {
+  sportSendByte(0x03);
+  RTOS_WAIT_MS(20);
+  sportSendByte(0x02);
+  RTOS_WAIT_MS(20);
   sportSendByte(0x01);
 
   for (uint8_t i = 0; i < 30; i++)
@@ -582,6 +586,7 @@ const char * FrskyChipFirmwareUpdate::startBootloader()
     sportSendByte(0x7F);
   }
 
+  RTOS_WAIT_MS(20);
   sportSendByte(0xFA);
 
   /*for (uint8_t i=0; i < 30; i++)
diff --git a/radio/src/targets/horus/telemetry_driver.cpp b/radio/src/targets/horus/telemetry_driver.cpp
index fe143cfe2..ecd73b6ab 100644
--- a/radio/src/targets/horus/telemetry_driver.cpp
+++ b/radio/src/targets/horus/telemetry_driver.cpp
@@ -228,8 +228,14 @@ void telemetryPortSetDirectionOutput()
   TELEMETRY_USART->CR1 &= ~USART_CR1_RE;                  // turn off receiver
 }
 
+void sportWaitTransmissionComplete()
+{
+  while (!(TELEMETRY_USART->SR & USART_SR_TC));
+}
+
 void telemetryPortSetDirectionInput()
 {
+  sportWaitTransmissionComplete();
   TELEMETRY_DIR_GPIO->BSRRH = TELEMETRY_DIR_GPIO_PIN;     // output disable
   TELEMETRY_USART->CR1 |= USART_CR1_RE;                   // turn on receiver
 }
-- 
2.11.4.GIT