Fix Modbus transmit enable GPIO

Fix Modbus transmit enable GPIO enabled once during write buffer

CHANGELOG.md

@@ -21,6 +21,7 @@ All notable changes to this project will be documented in this file.
 ### Fixed
 - Shutter default motorstop set to 0 (#17403)
 - Shutter default tilt configuration (#17484)
+- Modbus transmit enable GPIO enabled once during write buffer
 
 ### Removed
 

RELEASENOTES.md

@@ -111,8 +111,12 @@ The latter links can be used for OTA upgrades too like ``OtaUrl https://ota.tasm
 ### Added
 - Support for up to 3 single phase modbus energy monitoring device using generic Energy Modbus driver- Support for RGB displays [#17414](https://github.com/arendst/Tasmota/issues/17414)
 - Support for IPv6 DNS records (AAAA) and IPv6 ``Ping`` for ESP32 and ESP8266 [#17417](https://github.com/arendst/Tasmota/issues/17417)
+- Support for IPv6 only networks on Ethernet (not yet Wifi)
 - Berry support for ``crypto.SHA256`` [#17430](https://github.com/arendst/Tasmota/issues/17430)
 - Berry crypto add ``EC_P256`` and ``PBKDF2_HMAC_SHA256`` algorithms required by Matter protocol [#17473](https://github.com/arendst/Tasmota/issues/17473)
+- Berry crypto add ``random`` to generate series of random bytes
+- Berry crypto add ``HKDF_HMAC_SHA256``
+- Berry crypto add ``SPAKE2P_Matter`` for Matter support
 
 ### Breaking Changed
 
@@ -122,6 +126,7 @@ The latter links can be used for OTA upgrades too like ``OtaUrl https://ota.tasm
 - Tasmota OTA scripts now support both unzipped and gzipped file uploads [#17378](https://github.com/arendst/Tasmota/issues/17378)
 
 ### Fixed
+- Modbus transmit enable GPIO enabled once during write buffer
 - Shutter default motorstop set to 0 [#17403](https://github.com/arendst/Tasmota/issues/17403)
 - Shutter default tilt configuration [#17484](https://github.com/arendst/Tasmota/issues/17484)
 

lib/default/TasmotaSerial-3.6.0/src/TasmotaSerial.cpp

@@ -46,7 +46,6 @@ static uint32_t tasmota_serial_uart_bitmap = 0;      // Assigned UARTs
 
 TasmotaSerial::TasmotaSerial(int receive_pin, int transmit_pin, int hardware_fallback, int nwmode, int buffer_size) {
   m_valid = false;
-  m_tx_enable_valid = false;
   m_hardserial = false;
   m_hardswap = false;
   m_overflow = false;
@@ -56,6 +55,7 @@ TasmotaSerial::TasmotaSerial(int receive_pin, int transmit_pin, int hardware_fal
   serial_buffer_size = buffer_size;
   m_rx_pin = receive_pin;
   m_tx_pin = transmit_pin;
+  m_tx_enable_pin = -1;
   m_in_pos = 0;
   m_out_pos = 0;
 #ifdef ESP8266
@@ -134,12 +134,9 @@ bool TasmotaSerial::isValidGPIOpin(int pin) {
 
 void TasmotaSerial::setTransmitEnablePin(int tx_enable_pin) {
   if ((tx_enable_pin > -1) && isValidGPIOpin(tx_enable_pin)) {
-    m_tx_enable_valid = true;
     m_tx_enable_pin = tx_enable_pin;
     pinMode(m_tx_enable_pin, OUTPUT);
     digitalWrite(m_tx_enable_pin, LOW);
-  } else {
-    m_tx_enable_valid = false;
   }
 }
 
@@ -425,7 +422,7 @@ void IRAM_ATTR TasmotaSerial::_fast_write(uint8_t b) {
 size_t TasmotaSerial::write(uint8_t b) {
   if (!m_hardserial && (-1 == m_tx_pin)) { return 0; }
 
-  if (m_tx_enable_valid) {
+  if (m_tx_enable_pin > -1) {
     digitalWrite(m_tx_enable_pin, HIGH);
   }
   size_t size = 0;
@@ -462,7 +459,7 @@ size_t TasmotaSerial::write(uint8_t b) {
     }
     size = 1;
   }
-  if (m_tx_enable_valid) {
+  if (m_tx_enable_pin > -1) {
     delay(1);
     digitalWrite(m_tx_enable_pin, LOW);
   }

lib/default/TasmotaSerial-3.6.0/src/TasmotaSerial.h

@@ -95,7 +95,6 @@ class TasmotaSerial : public Stream {
     uint32_t m_out_pos;
     uint32_t serial_buffer_size = TM_SERIAL_BUFFER_SIZE;
     bool m_valid;
-    bool m_tx_enable_valid;
     bool m_nwmode;
     bool m_hardserial;
     bool m_hardswap;

lib/lib_basic/TasmotaModbus-3.6.0/src/TasmotaModbus.cpp

@@ -29,7 +29,13 @@ enum LoggingLevels {LOG_LEVEL_NONE, LOG_LEVEL_ERROR, LOG_LEVEL_INFO, LOG_LEVEL_D
 
 TasmotaModbus::TasmotaModbus(int receive_pin, int transmit_pin, int tx_enable_pin) : TasmotaSerial(receive_pin, transmit_pin, 2)
 {
-  setTransmitEnablePin(tx_enable_pin);
+//  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;
 }
 
@@ -150,7 +156,14 @@ uint8_t TasmotaModbus::Send(uint8_t device_address, uint8_t function_code, uint1
 #endif
 
   flush();
+  if (mb_tx_enable_pin > -1) {
+    digitalWrite(mb_tx_enable_pin, HIGH);
+  }
   write(frame, framepointer);
+  if (mb_tx_enable_pin > -1) {
+    delay(1);
+    digitalWrite(mb_tx_enable_pin, LOW);
+  }
   free(frame);
   return 0;
 }

lib/lib_basic/TasmotaModbus-3.6.0/src/TasmotaModbus.h

@@ -66,6 +66,7 @@ class TasmotaModbus : public TasmotaSerial {
     uint8_t ReceiveCount(void) { return mb_len; }
 
   private:
+    int mb_tx_enable_pin;
     uint8_t mb_address;
     uint8_t mb_len;
 };