0.2.1 RS485

libraries/RS485/README.md

@@ -37,6 +37,11 @@ The library sets the pinMode and defaults it to LOW (receiving mode).
 - **void     setMicrosPerByte(uint32_t baudRate)** set the delay per character needed.
 This gives the hardware enough time to flush the buffer. 
 - **uint32_t getMicrosPerByte()** returns the current delay in micros used.
+- **void setTXmode()** explicitly set mode to transmitting / sending.
+This implies that the device will stop listening on the RS485 bus.
+- **void setRXmode()** explicitly set mode to receiving / listening.
+This is the default behaviour of every RS485 device.
+- **uint8_t getMode()** returns the current mode, 1 == TX, 0 == RX.
 
 
 #### Stream interface
@@ -70,7 +75,6 @@ resumes with listening.
   - dynamic buffer size?
   - should this be a sort of message class / struct. fixed size?
 - add **yield()** for large messages that are blocking.
-- **stopListening()** and **startListening()** (with sendPin ?)
 - prevent blocking if possible.
 - add examples
 - add unit tests

libraries/RS485/RS485.cpp

@@ -2,13 +2,14 @@
 //    FILE: RS485.cpp
 //  AUTHOR: Rob Tillaart
 //    DATE: 30-okt-2017
-// VERSION: 0.2.0
+// VERSION: 0.2.1
 // PURPOSE: Arduino library for RS485 modules (MAX485)
 //     URL: https://github.com/RobTillaart/RS485
 //
 // HISTORY:
 // 0.1.x    2017-10-30  experimental versions.
 // 0.2.0    2022-05-24  first published version
+// 0.2.1    2022-05-24  add setTXmode(), setRXmode(), getMode().
 
 
 #include "RS485.h"
@@ -24,7 +25,7 @@ RS485::RS485(Stream * stream, uint8_t sendPin, uint8_t deviceID)
   _deviceID = deviceID;
   
   pinMode(_sendPin, OUTPUT);
-  digitalWrite(_sendPin, LOW);   //  receiver mode
+  setRXmode();    //  receiver mode
 }
 
 
@@ -50,20 +51,20 @@ void RS485::flush()
 
 size_t RS485::write(uint8_t c)
 {
-  digitalWrite(_sendPin, HIGH);   //  transmit mode
+  setTXmode();    //  transmit mode
   size_t n = _stream->write(c);
   delayMicroseconds(_microsPerByte);
-  digitalWrite(_sendPin, LOW);    //  receiver mode
+  setRXmode();    //  receiver mode
   return n;
 }
 
 //  TODO: fix blocking - yield() - merge above
 size_t RS485::write(uint8_t * array, uint8_t length)
 {
-  digitalWrite(_sendPin, HIGH);   //  transmit mode
+  setTXmode();    //  transmit mode
   size_t n = _stream->write(array, length);
   delayMicroseconds(_microsPerByte);
-  digitalWrite(_sendPin, LOW);    //  receiver mode
+  setRXmode();    //  receiver mode
   return n;
 }
 

libraries/RS485/RS485.h

@@ -3,7 +3,7 @@
 //    FILE: RS485.h
 //  AUTHOR: Rob Tillaart
 //    DATE: 30-okt-2017
-// VERSION: 0.2.0
+// VERSION: 0.2.1
 // PURPOSE: Arduino library for RS485 modules
 //     URL: https://github.com/RobTillaart/RS485
 
@@ -11,7 +11,7 @@
 #include "Arduino.h"
 #include "ASCII_CONTROL.h"
 
-#define RS485_LIB_VERSION "0.2.0"
+#define RS485_LIB_VERSION      (F("0.2.1"))
 
 
 class RS485 : public Stream
@@ -28,13 +28,18 @@ public:
   uint8_t  getDeviceID()      { return _deviceID; };
 
 
-  //     Stream interface
-  int    available();
-  int    read();
-  int    peek();
-  void   flush();
-  size_t write(uint8_t c);
-  size_t write(uint8_t * array, uint8_t length);
+  //       Stream interface
+  int      available();
+  int      read();
+  int      peek();
+  void     flush();
+  size_t   write(uint8_t c);
+  size_t   write(uint8_t * array, uint8_t length);
+
+  //  set the communication direction
+  inline void setTXmode() { digitalWrite(_sendPin, HIGH); };
+  inline void setRXmode() { digitalWrite(_sendPin, LOW); };
+  uint8_t     getMode()   { return digitalRead(_sendPin) == HIGH; };
 
 
   //  TODO TEST 0.3.0

libraries/RS485/library.json

@@ -15,7 +15,7 @@
     "type": "git",
     "url": "https://github.com/RobTillaart/RS485"
   },
-  "version": "0.2.0",
+  "version": "0.2.1",
   "license": "MIT",
   "frameworks": "arduino",
   "platforms": "*",

libraries/RS485/library.properties

@@ -1,5 +1,5 @@
 name=RS485
-version=0.2.0
+version=0.2.1
 author=Rob Tillaart <rob.tillaart@gmail.com>
 maintainer=Rob Tillaart <rob.tillaart@gmail.com>
 sentence=RS485 library for Arduino.

libraries/RS485/test/unit_test_001.cpp

@@ -74,12 +74,29 @@ unittest(test_microsPerByte)
   assertEqual(1000, master.getMicrosPerByte());
 
   master.setMicrosPerByte(115200);
-  // count 11 bits / byte
+  //  count 11 bits / byte
   uint32_t us = (11 * 1000000UL) / 115200;
   assertEqual(us, master.getMicrosPerByte());
 }
 
 
+unittest(test_communication_mode)
+{
+  Serial.begin(115200);
+
+  const uint8_t sendPin  = 4;
+
+  RS485 master(&Serial, sendPin);
+
+  //  default value
+  assertEqual(0, master.getMode());
+  master.setTXmode();
+  assertEqual(1, master.getMode());
+  master.setRXmode();
+  assertEqual(0, master.getMode());
+}
+
+
 unittest_main()
 
 // --------