Diff: SSD1306I2C.h

Revision:

0:56dd5df33ab4

Child:

1:9270c15c6aea

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/SSD1306I2C.h	Wed Apr 10 14:15:31 2019 +0000
@@ -0,0 +1,154 @@
+/**
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019 by Helmut Tschemernjak - www.radioshuttle.de
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * ThingPulse invests considerable time and money to develop these open source libraries.
+ * Please support us by buying our products (and not the clones) from
+ * https://thingpulse.com
+ *
+ */
+
+#ifndef SSD1306I2C_h
+#define SSD1306I2C_h
+
+
+#ifdef __MBED__
+
+#include "OLEDDisplay.h"
+#include <mbed.h>
+
+#ifndef UINT8_MAX
+ #define UINT8_MAX 0xff
+#endif
+
+class SSD1306I2C : public OLEDDisplay {
+public:
+    SSD1306I2C(uint8_t _address, PinName _sda, PinName _scl, OLEDDISPLAY_GEOMETRY g = GEOMETRY_128_64) {
+      setGeometry(g);
+
+      this->_address = _address << 1;  // convert from 7 to 8 bit for mbed.
+      this->_sda = _sda;
+      this->_scl = _scl;
+	  _i2c = new I2C(_sda, _scl);
+    }
+
+    bool connect() {
+		// mbed supports 100k and 400k some device maybe 1000k
+#ifdef TARGET_STM32L4
+	  _i2c->frequency(1000000);
+#else
+	  _i2c->frequency(400000);
+#endif
+      return true;
+    }
+
+    void display(void) {
+      const int x_offset = (128 - this->width()) / 2;
+#ifdef OLEDDISPLAY_DOUBLE_BUFFER
+        uint8_t minBoundY = UINT8_MAX;
+        uint8_t maxBoundY = 0;
+
+        uint8_t minBoundX = UINT8_MAX;
+        uint8_t maxBoundX = 0;
+        uint8_t x, y;
+
+        // Calculate the Y bounding box of changes
+        // and copy buffer[pos] to buffer_back[pos];
+        for (y = 0; y < (this->height() / 8); y++) {
+          for (x = 0; x < this->width(); x++) {
+           uint16_t pos = x + y * this->width();
+           if (buffer[pos] != buffer_back[pos]) {
+             minBoundY = std::min(minBoundY, y);
+             maxBoundY = std::max(maxBoundY, y);
+             minBoundX = std::min(minBoundX, x);
+             maxBoundX = std::max(maxBoundX, x);
+           }
+           buffer_back[pos] = buffer[pos];
+         }
+         yield();
+        }
+
+        // If the minBoundY wasn't updated
+        // we can savely assume that buffer_back[pos] == buffer[pos]
+        // holdes true for all values of pos
+
+        if (minBoundY == UINT8_MAX) return;
+
+        sendCommand(COLUMNADDR);
+        sendCommand(x_offset + minBoundX);	// column start address (0 = reset)
+        sendCommand(x_offset + maxBoundX);	// column end address (127 = reset)
+
+        sendCommand(PAGEADDR);
+        sendCommand(minBoundY);				// page start address
+        sendCommand(maxBoundY);				// page end address
+
+        for (y = minBoundY; y <= maxBoundY; y++) {
+			uint8_t *start = &buffer[(minBoundX + y * this->width())-1];
+			uint8_t save = *start;
+			
+			*start = 0x40; // control
+			_i2c->write(_address, (char *)start, (maxBoundX-minBoundX) + 1 + 1);
+			*start = save;
+		}
+#else
+
+        sendCommand(COLUMNADDR);
+        sendCommand(x_offset);						// column start address (0 = reset)
+        sendCommand(x_offset + (this->width() - 1));// column end address (127 = reset)
+
+        sendCommand(PAGEADDR);
+        sendCommand(0x0);							// page start address (0 = reset)
+        sendCommand((this->height() / 8) - 1);		// page end address 7
+
+        if (geometry == GEOMETRY_128_64) {
+          sendCommand(0x7);
+        } else if (geometry == GEOMETRY_128_32) {
+          sendCommand(0x3);
+        }
+
+		buffer[-1] = 0x40; // control
+		_i2c->write(_address, (char *)&buffer[-1], displayBufferSize + 1);
+#endif
+    }
+
+private:
+	int getBufferOffset(void) {
+		return 0;
+	}
+
+    inline void sendCommand(uint8_t command) __attribute__((always_inline)) {
+		char _data[2];
+	  	_data[0] = 0x80; // control
+	  	_data[1] = command;
+	  	_i2c->write(_address, _data, sizeof(_data));
+    }
+
+	uint8_t             _address;
+	PinName             _sda;
+	PinName             _scl;
+	I2C *_i2c;
+};
+
+#endif
+
+#endif
+