added example; small line cleanup

Author: kikass13

examples/stm32f4_discovery/can_m2515/main.cpp

@@ -0,0 +1,99 @@
+/*
+ * Copyright (c) 2013, Kevin Läufer
+ * Copyright (c) 2013-2017, Niklas Hauser
+ * Copyright (c) 2016, Raphael Lehmann
+ *
+ * This file is part of the modm project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+// ----------------------------------------------------------------------------
+
+#include <modm/board.hpp>
+#include <modm/driver/can/mcp2515.hpp>
+#include <modm/processing/protothread.hpp>
+
+// If you use a different SPI instance, you may have to also choose different
+// GPIOs to connect to.
+using Int = GpioOutputB11;
+using Cs = GpioOutputB12;
+using Sck = GpioOutputB13;
+using Mosi = GpioOutputB15;
+using Miso = GpioInputB14;
+using SpiMaster = SpiMaster2;
+// Note that you can also use a bit-banged SPI driver as a drop-in replacement
+// using SpiMaster = BitBangSpiMaster<Sck, Mosi, Miso>;
+
+// Default filters to receive any extended CAN frame
+FLASH_STORAGE(uint8_t canFilter[]) = {
+	MCP2515_FILTER_EXTENDED(0),  // Filter 0
+	MCP2515_FILTER_EXTENDED(0),  // Filter 1
+
+	MCP2515_FILTER_EXTENDED(0),  // Filter 2
+	MCP2515_FILTER_EXTENDED(0),  // Filter 3
+	MCP2515_FILTER_EXTENDED(0),  // Filter 4
+	MCP2515_FILTER_EXTENDED(0),  // Filter 5
+
+	MCP2515_FILTER_EXTENDED(0),  // Mask 0
+	MCP2515_FILTER_EXTENDED(0),  // Mask 1
+};
+
+modm::Mcp2515<SpiMaster, Cs, Int> mcp2515;
+
+class MyTask : modm::pt::Protothread
+{
+public:
+	MyTask() : message_{0x123456}
+	{
+		mcp2515.initialize<8_MHz, 125_kbps>();
+		mcp2515.setFilter(modm::accessor::asFlash(canFilter));
+	}
+
+	bool
+	run()
+	{
+		PT_BEGIN();
+		while (true)
+		{
+			// send a new message
+			message_.length = 2;
+			message_.data[0] = 0xab;
+			message_.data[1] = 0xcd;
+			mcp2515.sendMessage(message_);
+
+			if (mcp2515.isMessageAvailable())
+			{
+				mcp2515.getMessage(message_);
+				MODM_LOG_INFO << "Received message: " << message_.identifier << modm::endl;
+			}
+		}
+		PT_END();
+	}
+
+private:
+	modm::can::Message message_;
+};
+
+MyTask task;
+
+int
+main()
+{
+	Board::initialize();
+
+	// Initialize SPI interface and the other pins
+	// needed by the MCP2515
+	SpiMaster::connect<Miso::Miso, Mosi::Mosi, Sck::Sck>();
+	/// we initialize a higher baud rate then n the avr example, dunnow hats the mcp2515 is capable
+	/// of
+	SpiMaster::initialize<Board::SystemClock, 20_MHz>();
+	Cs::setOutput();
+	Int::setInput(Gpio::InputType::PullUp);
+
+	// Configure MCP2515 and set the filters
+	mcp2515.initialize<8_MHz, 125_kbps>();
+
+	while (true) { task.run(); }
+}

examples/stm32f4_discovery/can_m2515/project.xml

@@ -0,0 +1,18 @@
+<library>
+  <extends>modm:disco-f407vg</extends>
+  <options>
+    <option name="modm:build:build.path">../../../build/stm32f4_discovery/spi</option>
+  </options>
+  <modules>
+    <module>modm:platform:gpio</module>
+    <module>modm:platform:spi.bitbang</module>
+    <module>modm:platform:spi:2</module>
+    <module>modm:build:scons</module>
+
+
+    <module>modm:processing:protothread</module>
+    <module>modm:processing:timer</module>
+    <module>modm:driver:mcp2515</module>
+
+  </modules>
+</library>

src/modm/driver/can/mcp2515_impl.hpp

@@ -124,7 +124,6 @@ modm::Mcp2515<SPI, CS, INT>::initialize()
 	using Timings = modm::CanBitTimingMcp2515<externalClockFrequency, bitrate>;
 
 	// initialize interrrupt on INT pin
-
 	modm::platform::Exti::connect<INT>(modm::platform::Exti::Trigger::FallingEdge, [](uint8_t){
 		mcp2515interrupt();
 	});
@@ -146,8 +145,7 @@ modm::Mcp2515<SPI, CS, INT>::setFilter(accessor::Flash<uint8_t> filter)
 
 	// change to configuration mode
 	bitModify(CANCTRL, 0xe0, REQOP2);
-	while ((readRegister(CANSTAT) & 0xe0) != REQOP2)
-		;
+	while ((readRegister(CANSTAT) & 0xe0) != REQOP2);
 
 	writeRegister(RXB0CTRL, BUKT);
 	writeRegister(RXB1CTRL, 0);