Refactor RS485 support

Author: manchoz

.github/workflows/compile-examples.yml

@@ -42,6 +42,11 @@ jobs:
           fqbn: arduino:mbed_portenta:envie_m7
           platforms: |
             - name: arduino:mbed_portenta
+          libraries: |
+            - source-path: ./
+            - name: ArduinoRS485
+          sketch-paths: |
+            - examples            
           enable-deltas-report: true
           enable-warnings-report: true
           sketches-report-path: ${{ env.SKETCHES_REPORTS_PATH }}

examples/RS485_fullduplex/RS485_fullduplex.ino

@@ -2,21 +2,25 @@
   RS485 Full duplex communication
 
   This sketch shows how to use the SP335ECR1 on the Machine
-  Control as a full duplex RS485 interface, how to periodically
+  Control as a full duplex (AB and YZ) RS485 interface, how to periodically
   send a string on the RS485 TX channel and how to receive data
   from the interface RX channel.
 
   Circuit:
    - Portenta H7
    - Machine Control
    - A Slave device with RS485 interface
+   - Connect TXP to A(+) and TXN to B(-)
+   - Connect RXP to Y(+) and RXN to Z(-)
 
 */
 
 #include "Arduino_MachineControl.h"
 
 using namespace machinecontrol;
 
+constexpr unsigned long sendInterval { 1000 };
+unsigned long sendNow { 0 };
 unsigned long counter = 0;
 
 void setup()
@@ -29,37 +33,47 @@ void setup()
     delay(1000);
     Serial.println("Start RS485 initialization");
 
-    comm_protocols.rs485.begin(115200);
-    comm_protocols.rs485.enable = 1;        // SDHN_N
-    comm_protocols.rs485.sel_485 = 1;       // RS485_RS232_N
-    comm_protocols.rs485.half_duplex = 0;   // HALF_FULL_N
-    comm_protocols.rs485.receive();         // RE_N
-    comm_protocols.rs485.fd_tx_term = 1;    // FD_TX_TERM - 120 ohm Y-Z termination enabled when both TERM and FD_TX_TERM are high
-    comm_protocols.rs485.term = 1;          // TERM - 120 ohm A-B termination enabled when high
+    // Set the PMC Communication Protocols to default config
+    comm_protocols.init();
+    // RS485/RS232 default config is:
+    // - RS485 mode
+    // - Half Duplex
+    // - No A/B and Y/Z 120 Ohm termination enabled
+
+    // Enable the RS485/RS232 system
+    comm_protocols.rs485Enable(true);
+
+    // Enable Full Duplex mode
+    // This will also enable A/B and Y/Z 120 Ohm termination resistors
+    comm_protocols.rs485FullDuplex(true);
+    
+    // Specify baudrate, and preamble and postamble times for RS485 communication
+    comm_protocols.rs485.begin(115200, 0, 500);
+    
+    // Start in receive mode
+    comm_protocols.rs485.receive();
+    
 
     Serial.println("Initialization done!");
 }
 
-constexpr unsigned long sendInterval { 1000 };
-unsigned long sendNow { 0 };
-
-constexpr unsigned long halfFullInterval { 5000 };
-unsigned long halfFull { 0 };
-byte halfFullStatus { 0 };
-
 void loop()
 {
-    while (comm_protocols.rs485.available())
+    if (comm_protocols.rs485.available())
         Serial.write(comm_protocols.rs485.read());
 
     if (millis() > sendNow) {
+        // Disable receive mode before transmission
         comm_protocols.rs485.noReceive();
+
         comm_protocols.rs485.beginTransmission();
 
         comm_protocols.rs485.print("hello ");
         comm_protocols.rs485.println(counter++);
 
         comm_protocols.rs485.endTransmission();
+        
+        // Re-enable receive mode after transmission
         comm_protocols.rs485.receive();
 
         sendNow = millis() + sendInterval;

examples/RS485_halfduplex/RS485_halfduplex.ino

@@ -0,0 +1,77 @@
+/*
+  RS485 Half Duplex communication
+
+  This sketch shows how to use the SP335ECR1 on the Machine
+  Control as a half duplex (AB) RS485 interface, how to periodically
+  send a string on the RS485 TX channel and how to receive data
+  from the interface RX channel.
+
+  Circuit:
+   - Portenta H7
+   - Machine Control
+   - A Slave device with RS485 interface
+   - Connect TXP to A(+) and TXN to B(-)
+
+*/
+
+#include "Arduino_MachineControl.h"
+
+using namespace machinecontrol;
+
+constexpr unsigned long sendInterval { 1000 };
+unsigned long sendNow { 0 };
+
+unsigned long counter { 0 };
+
+void setup()
+{
+
+    Serial.begin(115200);
+    // Wait for Serial or start after 2.5s
+    for (auto const timeout = millis() + 2500; !Serial && timeout < millis(); delay(500))
+        ;
+
+    delay(2500);
+    Serial.println("Start RS485 initialization");
+
+    // Set the PMC Communication Protocols to default config
+    comm_protocols.init();
+
+    // RS485/RS232 default config is:
+    // - RS485 mode
+    // - Half Duplex
+    // - No A/B and Y/Z 120 Ohm termination enabled
+
+    // Enable the RS485/RS232 system
+    comm_protocols.rs485Enable(true);
+
+    // Specify baudrate, and preamble and postamble times for RS485 communication
+    comm_protocols.rs485.begin(115200, 0, 500);
+    // Start in receive mode
+    comm_protocols.rs485.receive();
+
+    Serial.println("Initialization done!");
+}
+
+void loop()
+{
+    if (comm_protocols.rs485.available())
+        Serial.write(comm_protocols.rs485.read());
+
+    if (millis() > sendNow) {
+        // Disable receive mode before transmission
+        comm_protocols.rs485.noReceive();
+
+        comm_protocols.rs485.beginTransmission();
+
+        comm_protocols.rs485.print("hello ");
+        comm_protocols.rs485.println(counter++);
+
+        comm_protocols.rs485.endTransmission();
+
+        // Re-enable receive mode after transmission
+        comm_protocols.rs485.receive();
+
+        sendNow = millis() + sendInterval;
+    }
+}

library.properties

@@ -8,3 +8,4 @@ category=Communication
 url=https://github.com/arduino-libraries/Arduino_MachineControl
 architectures=mbed, mbed_portenta
 includes=Arduino_MachineControl.h
+depends=ArduinoRS485

src/Arduino_MachineControl.h

@@ -3,13 +3,14 @@
 
 #include "utility/MAX31865/MAX31865.h"
 #include "utility/THERMOCOUPLE/MAX31855.h"
-#include "utility/RS485/RS485.h"
+#include <ArduinoRS485.h>
 #include "utility/QEI/QEI.h"
 #include "utility/ioexpander/ArduinoIOExpander.h"
 #include "utility/RTC/PCF8563T.h"
 #include "utility/RTC/PCF8563T.h"
 
 #include "Arduino.h"
+#include "pinDefinitions.h"
 #include "mbed.h"
 
 #include "USBHost.h"
@@ -57,11 +58,19 @@ class COMMClass {
 	// to be tested: check if can be made a big pin initialization
 	void init() {
 		//SHUTDOWN OF RS485 LEDS
-		digitalWrite(PA_0, LOW);
-		digitalWrite(PI_9, LOW);
+		digitalWrite(PinNameToIndex(PA_0), LOW);
+		digitalWrite(PinNameToIndex(PI_9), LOW);
 		//SHUTDOWN OF CAN LEDS
-		digitalWrite(PB_8, LOW);
-		digitalWrite(PH_13, LOW);
+		digitalWrite(PinNameToIndex(PB_8), LOW);
+		digitalWrite(PinNameToIndex(PH_13), LOW);
+
+		// SET DEFAULTS for RS485
+		rs485Enable(false);
+		rs485ModeRS232(false);
+		rs485FullDuplex(false);
+		rs485YZTerm(false);
+		rs485ABTerm(false);
+		rs485Slew(false);
 	}
 
 	void enableCAN() {
@@ -74,11 +83,24 @@ class COMMClass {
 	UART _UART4_ = arduino::UART(PA_0, PI_9, NC, NC);
 	mbed::CAN& can = _can;
 
-	RS485Class rs485 = RS485Class(_UART4_,PA_0, PI_13,PI_10);
+	RS485Class rs485 = RS485Class(_UART4_, PinNameToIndex(PA_0), PinNameToIndex(PI_13), PinNameToIndex(PI_10));
+
+	void rs485Enable(bool enable) 		{ digitalWrite(PinNameToIndex(PG_9),  enable ? 	HIGH : LOW); }
+	void rs485ModeRS232(bool enable) 	{ digitalWrite(PinNameToIndex(PA_10), enable ? 	LOW : HIGH); }
+	void rs485YZTerm(bool enable) 		{ digitalWrite(PinNameToIndex(PI_15), enable ? 	HIGH : LOW); }
+	void rs485ABTerm(bool enable) 		{ digitalWrite(PinNameToIndex(PI_14), enable ? 	HIGH : LOW); }
+    void rs485Slew(bool enable)  		{ digitalWrite(PinNameToIndex(PG_14), enable ? 	LOW : HIGH); }
+	void rs485FullDuplex(bool enable) 	{
+		digitalWrite(PinNameToIndex(PA_9), enable ? LOW : HIGH);
+		if (enable) {
+			// RS485 Full Duplex require YZ and AB 120 Ohm termination enabled
+			rs485YZTerm(true);
+			rs485ABTerm(true);
+		}
+	}
+
 private:
 	mbed::DigitalOut can_disable = mbed::DigitalOut(PA_13, 0);
-
-
 };
 
 extern COMMClass comm_protocols;