update changelog, improve docs and default values for #74

changelog.md

@@ -15,6 +15,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 <!-- ## [Unreleased] -->
 
 ## Released
+## [2.4.0] - 2023-07-02
+### Added
+- The following fixes were provided by @sandyscott
+- UART signals can be inverted with the `invert` argument of the `Serial` and `ModbusRTU` class constructors
+
 ## [2.3.5] - 2023-07-01
 ### Fixed
 - Time between RS485 control pin raise and UART transmission reduced by 80% from 1000us to 200us
@@ -290,8 +295,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - PEP8 style issues on all files of [`lib/uModbus`](lib/uModbus)
 
 <!-- Links -->
-[Unreleased]: https://github.com/brainelectronics/micropython-modbus/compare/2.3.5...develop
+[Unreleased]: https://github.com/brainelectronics/micropython-modbus/compare/2.4.0...develop
 
+[2.4.0]: https://github.com/brainelectronics/micropython-modbus/tree/2.4.0
 [2.3.5]: https://github.com/brainelectronics/micropython-modbus/tree/2.3.5
 [2.3.4]: https://github.com/brainelectronics/micropython-modbus/tree/2.3.4
 [2.3.3]: https://github.com/brainelectronics/micropython-modbus/tree/2.3.3

fakes/machine.py

@@ -27,6 +27,11 @@ class UART(object):
 
     See https://docs.micropython.org/en/latest/library/machine.UART.html
     """
+    # ESP32: TX=32, RX=4
+    # RP2: TX=1, RX=2
+    INV_RX = 4
+    INV_TX = 32
+
     def __init__(self,
                  uart_id: int,
                  baudrate: int = 9600,
@@ -35,7 +40,8 @@ def __init__(self,
                  stop: int = 1,
                  tx: int = 1,
                  rx: int = 2,
-                 timeout: int = 0) -> None:
+                 timeout: int = 0,
+                 invert: int = 0) -> None:
         self._uart_id = uart_id
         if timeout == 0:
             timeout = 5.0

umodbus/serial.py

@@ -26,9 +26,10 @@
 
 
 class ModbusRTU(Modbus):
-    INV_RX = UART.INV_RX  # Include in class so they can be used when creating the object
+    # Include in class so they can be used when creating the object
+    INV_RX = UART.INV_RX
     INV_TX = UART.INV_TX
-    
+
     """
     Modbus RTU client class
 
@@ -61,7 +62,7 @@ def __init__(self,
                  pins: List[Union[int, Pin], Union[int, Pin]] = None,
                  ctrl_pin: int = None,
                  uart_id: int = 1,
-                 invert: int = None):
+                 invert: int = 0):
         super().__init__(
             # set itf to Serial object, addr_list to [addr]
             Serial(uart_id=uart_id,
@@ -77,9 +78,10 @@ def __init__(self,
 
 
 class Serial(CommonModbusFunctions):
-    INV_RX = UART.INV_RX  # Include in class so they can be used when creating the object
+    # Include in class so they can be used when creating the object
+    INV_RX = UART.INV_RX
     INV_TX = UART.INV_TX
-    
+
     def __init__(self,
                  uart_id: int = 1,
                  baudrate: int = 9600,
@@ -88,7 +90,7 @@ def __init__(self,
                  parity=None,
                  pins: List[Union[int, Pin], Union[int, Pin]] = None,
                  ctrl_pin: int = None,
-                 invert: int = None):
+                 invert: int = 0):
         """
         Setup Serial/RTU Modbus
 
@@ -106,6 +108,8 @@ def __init__(self,
         :type       pins:        List[Union[int, Pin], Union[int, Pin]]
         :param      ctrl_pin:    The control pin
         :type       ctrl_pin:    int
+        :param      invert:      Invert TX and/or RX pins
+        :type       invert:      int
         """
         # UART flush function is introduced in Micropython v1.20.0
         self._has_uart_flush = callable(getattr(UART, "flush", None))