From 8ced0579d636d88ab7ed6bbfbcce51b14ae97636 Mon Sep 17 00:00:00 2001
From: Alex Voinea <voinea.dragos.alexandru@gmail.com>
Date: Wed, 3 Mar 2021 14:35:37 +0200
Subject: [PATCH] Move SerialHead declaration outside of loops

---
 Firmware/optiboot_w25x20cl.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Firmware/optiboot_w25x20cl.cpp b/Firmware/optiboot_w25x20cl.cpp
index 05ae8931f..9e2296e7c 100644
--- a/Firmware/optiboot_w25x20cl.cpp
+++ b/Firmware/optiboot_w25x20cl.cpp
@@ -126,6 +126,7 @@ uint8_t optiboot_w25x20cl_enter()
     }
     selectedSerialPort = 0; //switch to Serial0
     MYSERIAL.flush(); //clear RX buffer
+    int SerialHead = rx_buffer.head;
     // Send the initial magic string.
     while (ptr != end)
       putch(pgm_read_byte(ptr ++));
@@ -143,7 +144,6 @@ uint8_t optiboot_w25x20cl_enter()
       // With the volatile keyword the compiler generates exactly the same code as without it with only one difference:
       // the last brne instruction jumps onto the (*rx_head == SerialHead) check and NOT onto the wdr instruction bypassing the check.
       volatile int *rx_head = &rx_buffer.head;
-      int SerialHead = rx_buffer.head;
       while (*rx_head == SerialHead) {
         wdt_reset();
         if ( --boot_timer == 0) {