From c1484f761c9827cb9e3904641f958eefd10d5810 Mon Sep 17 00:00:00 2001
From: Theo Arends <11044339+arendst@users.noreply.github.com>
Date: Wed, 28 Dec 2022 15:19:09 +0100
Subject: [PATCH] Fix exception 9 when modbus tx enable is used

---
 lib/default/TasmotaSerial-3.6.0/src/TasmotaSerial.cpp |  2 +-
 .../TasmotaModbus-3.6.0/src/TasmotaModbus.cpp         | 11 +++++------
 2 files changed, 6 insertions(+), 7 deletions(-)

diff --git a/lib/default/TasmotaSerial-3.6.0/src/TasmotaSerial.cpp b/lib/default/TasmotaSerial-3.6.0/src/TasmotaSerial.cpp
index d690c62eb..20654b05f 100644
--- a/lib/default/TasmotaSerial-3.6.0/src/TasmotaSerial.cpp
+++ b/lib/default/TasmotaSerial-3.6.0/src/TasmotaSerial.cpp
@@ -460,7 +460,7 @@ size_t TasmotaSerial::write(uint8_t b) {
     size = 1;
   }
   if (m_tx_enable_pin > -1) {
-    delay(1);
+    delayMicroseconds(800);  // delay(1) will exception here
     digitalWrite(m_tx_enable_pin, LOW);
   }
   return size;
diff --git a/lib/lib_basic/TasmotaModbus-3.6.0/src/TasmotaModbus.cpp b/lib/lib_basic/TasmotaModbus-3.6.0/src/TasmotaModbus.cpp
index baf66f8b0..0fb316bd3 100644
--- a/lib/lib_basic/TasmotaModbus-3.6.0/src/TasmotaModbus.cpp
+++ b/lib/lib_basic/TasmotaModbus-3.6.0/src/TasmotaModbus.cpp
@@ -31,11 +31,6 @@ TasmotaModbus::TasmotaModbus(int receive_pin, int transmit_pin, int tx_enable_pi
 {
 //  setTransmitEnablePin(tx_enable_pin);
   mb_tx_enable_pin = tx_enable_pin;
-  if (mb_tx_enable_pin > -1) {
-    pinMode(mb_tx_enable_pin, OUTPUT);
-    digitalWrite(mb_tx_enable_pin, LOW);
-  }
-
   mb_address = 0;
 }
 
@@ -64,6 +59,10 @@ int TasmotaModbus::Begin(long speed, uint32_t config)
   if (begin(speed, config)) {
     result = 1;
     if (hardwareSerial()) { result = 2; }
+    if (mb_tx_enable_pin > -1) {
+      pinMode(mb_tx_enable_pin, OUTPUT);
+      digitalWrite(mb_tx_enable_pin, LOW);
+    }
   }
   return result;
 }
@@ -161,7 +160,7 @@ uint8_t TasmotaModbus::Send(uint8_t device_address, uint8_t function_code, uint1
   }
   write(frame, framepointer);
   if (mb_tx_enable_pin > -1) {
-    delay(1);
+    delayMicroseconds(800);  // delay(1) will exception here
     digitalWrite(mb_tx_enable_pin, LOW);
   }
   free(frame);