From 84260dcb44dea9a5c73762ac018e46e400c30edf Mon Sep 17 00:00:00 2001
From: "Dirk O. Kaar" <19971886+dok-net@users.noreply.github.com>
Date: Thu, 31 Dec 2020 01:05:20 +0100
Subject: [PATCH] Write loop could lead to wdt with low bitrates or large
 buffers. Fixes #7746 (#7799)

---
 cores/esp8266/uart.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/cores/esp8266/uart.cpp b/cores/esp8266/uart.cpp
index a21300e51..47e7243ab 100644
--- a/cores/esp8266/uart.cpp
+++ b/cores/esp8266/uart.cpp
@@ -506,8 +506,10 @@ uart_write(uart_t* uart, const char* buf, size_t size)
 
     size_t ret = size;
     const int uart_nr = uart->uart_nr;
-    while (size--)
+    while (size--) {
         uart_do_write_char(uart_nr, pgm_read_byte(buf++));
+        optimistic_yield(10000UL);
+    }
 
     return ret;
 }