Add driver for SSD1306 OLED display on raspberry pi

1 files changed, 340 insertions, 0 deletions

diff --git a/glcddrivers/ssd1306.c b/glcddrivers/ssd1306.c
new file mode 100644
index 0000000..852ea13
--- /dev/null
+++ b/glcddrivers/ssd1306.c
@@ -0,0 +1,340 @@
+/*
+ * GraphLCD driver library
+ *
+ * ssd1306.c  -  SSD1306 OLED driver class
+ *
+ * This file is released under the GNU General Public License. Refer
+ * to the COPYING file distributed with this package.
+ *
+ * (c) 2014 Andreas Regel <andreas.regel AT powarman.de>
+ */
+
+#include <stdint.h>
+#include <syslog.h>
+#include <unistd.h>
+#include <cstring>
+
+#include <wiringPi.h>
+#include <wiringPiSPI.h>
+
+#include "common.h"
+#include "config.h"
+#include "ssd1306.h"
+
+
+namespace GLCD
+{
+
+const int kLcdWidth  = 128;
+const int kLcdHeight = 64;
+
+const int kSpiBus    = 0;
+
+const int kGpioReset = 15;
+const int kGpioDC    = 16;
+
+const uint8_t kCmdSetLowerColumn            = 0x00;
+const uint8_t kCmdSetHigherColumn           = 0x10;
+const uint8_t kCmdSetMemoryAddressingMode   = 0x20;
+const uint8_t kCmdSetColumnAddress          = 0x21;
+const uint8_t kCmdSetPageAddress            = 0x22;
+const uint8_t kCmdSetDisplayStartLine       = 0x40;
+const uint8_t kCmdSetContrast               = 0x81;
+const uint8_t kCmdSetChargePump             = 0x8D;
+const uint8_t kCmdSetSegmentReMap           = 0xA0;
+const uint8_t kCmdEntireDisplayOnResume     = 0xA4;
+const uint8_t kCmdEntireDisplayOn           = 0xA5;
+const uint8_t kCmdSetNormalDisplay          = 0xA6;
+const uint8_t kCmdSetInverseDisplay         = 0xA7;
+const uint8_t kCmdSetMultiplexRatio         = 0xA8;
+const uint8_t kCmdSetDisplayOff             = 0xAE;
+const uint8_t kCmdSetDisplayOn              = 0xAF;
+const uint8_t kCmdSetPageStart              = 0xB0;
+const uint8_t kCmdSetComScanInc             = 0xC0;
+const uint8_t kCmdSetComScanDec             = 0xC8;
+const uint8_t kCmdSetDisplayOffset          = 0xD3;
+const uint8_t kCmdSetDisplayClockDiv        = 0xD5;
+const uint8_t kCmdSetPreChargePeriod        = 0xD9;
+const uint8_t kCmdSetComPins                = 0xDA;
+const uint8_t kCmdSetVComDeselectLevel      = 0xDB;
+
+
+cDriverSSD1306::cDriverSSD1306(cDriverConfig * config)
+:   cDriver(config)
+{
+    refreshCounter = 0;
+
+    wiringPiSetup();
+}
+
+cDriverSSD1306::~cDriverSSD1306()
+{
+    //delete port;
+}
+
+int cDriverSSD1306::Init()
+{
+    int x;
+
+    width = config->width;
+    if (width <= 0)
+        width = kLcdWidth;
+    height = config->height;
+    if (height <= 0)
+        height = kLcdHeight;
+
+    for (unsigned int i = 0; i < config->options.size(); i++)
+    {
+        if (config->options[i].name == "")
+        {
+        }
+    }
+
+    // setup lcd array (wanted state)
+    newLCD = new unsigned char*[width];
+    if (newLCD)
+    {
+        for (x = 0; x < width; x++)
+        {
+            newLCD[x] = new unsigned char[(height + 7) / 8];
+            memset(newLCD[x], 0, (height + 7) / 8);
+        }
+    }
+    // setup lcd array (current state)
+    oldLCD = new unsigned char*[width];
+    if (oldLCD)
+    {
+        for (x = 0; x < width; x++)
+        {
+            oldLCD[x] = new unsigned char[(height + 7) / 8];
+            memset(oldLCD[x], 0, (height + 7) / 8);
+        }
+    }
+
+    if (config->device == "")
+    {
+        return -1;
+    }
+
+    pinMode(kGpioReset, OUTPUT);
+    pinMode(kGpioDC, OUTPUT);
+
+    digitalWrite(kGpioReset, HIGH);
+    digitalWrite(kGpioDC, LOW);
+
+    wiringPiSPISetup(kSpiBus, 1000000);
+
+    /* reset display */
+    Reset();
+    usleep(1000);
+
+    WriteCommand(kCmdSetDisplayOff);
+
+    if (height == 64)
+    {
+        WriteCommand(kCmdSetMultiplexRatio, 0x3F);
+        WriteCommand(kCmdSetComPins, 0x12);
+    }
+    else if (height == 32)
+    {
+        WriteCommand(kCmdSetMultiplexRatio, 0x1F);
+        WriteCommand(kCmdSetComPins, 0x02);
+    }
+
+    WriteCommand(kCmdSetDisplayOffset, 0x00);
+    WriteCommand(kCmdSetDisplayStartLine | 0x00);
+    WriteCommand(kCmdSetMemoryAddressingMode, 0x01);
+    WriteCommand(kCmdSetSegmentReMap | 0x01);
+    WriteCommand(kCmdSetComScanDec);
+    WriteCommand(kCmdSetContrast, config->brightness * 255 / 100);
+    WriteCommand(kCmdEntireDisplayOnResume);
+    WriteCommand(kCmdSetNormalDisplay);
+    WriteCommand(kCmdSetDisplayClockDiv, 0x80);
+    WriteCommand(kCmdSetChargePump, 0x14);
+    WriteCommand(kCmdSetDisplayOn);
+
+    *oldConfig = *config;
+
+    // clear display
+    Clear();
+
+    syslog(LOG_INFO, "%s: SSD1306 initialized.\n", config->name.c_str());
+    return 0;
+}
+
+int cDriverSSD1306::DeInit()
+{
+    int x;
+    // free lcd array (wanted state)
+    if (newLCD)
+    {
+        for (x = 0; x < width; x++)
+        {
+            delete[] newLCD[x];
+        }
+        delete[] newLCD;
+    }
+    // free lcd array (current state)
+    if (oldLCD)
+    {
+        for (x = 0; x < width; x++)
+        {
+            delete[] oldLCD[x];
+        }
+        delete[] oldLCD;
+    }
+
+    return 0;
+}
+
+int cDriverSSD1306::CheckSetup()
+{
+    if (config->device != oldConfig->device ||
+        config->width != oldConfig->width ||
+        config->height != oldConfig->height)
+    {
+        DeInit();
+        Init();
+        return 0;
+    }
+
+    if (config->upsideDown != oldConfig->upsideDown ||
+        config->invert != oldConfig->invert)
+    {
+        oldConfig->upsideDown = config->upsideDown;
+        oldConfig->invert = config->invert;
+        return 1;
+    }
+    return 0;
+}
+
+void cDriverSSD1306::Clear()
+{
+    for (int x = 0; x < width; x++)
+        memset(newLCD[x], 0, (height + 7) / 8);
+}
+
+
+void cDriverSSD1306::SetPixel(int x, int y, uint32_t data)
+{
+    if (x >= width || y >= height)
+        return;
+
+    if (config->upsideDown)
+    {
+        x = width - 1 - x;
+        y = height - 1 - y;
+    }
+
+    int offset = (y % 8);
+    if (data == GRAPHLCD_White)
+        newLCD[x][y / 8] |= (1 << offset);
+    else
+        newLCD[x][y / 8] &= ( 0xFF ^ (1 << offset) );
+}
+
+
+#if 0
+void cDriverSSD1306::Set8Pixels(int x, int y, unsigned char data)
+{
+    if (x >= width || y >= height)
+        return;
+
+    if (!config->upsideDown)
+    {
+        int offset = 7 - (y % 8);
+        for (int i = 0; i < 8; i++)
+        {
+            newLCD[x + i][y / 8] |= ((data >> (7 - i)) << offset) & (1 << offset);
+        }
+    }
+    else
+    {
+        x = width - 1 - x;
+        y = height - 1 - y;
+        int offset = 7 - (y % 8);
+        for (int i = 0; i < 8; i++)
+        {
+            newLCD[x - i][y / 8] |= ((data >> (7 - i)) << offset) & (1 << offset);
+        }
+    }
+}
+#endif
+
+void cDriverSSD1306::Refresh(bool refreshAll)
+{
+    int x;
+    int y;
+    uint8_t numPages = (height + 7) / 8;
+    unsigned char data[16];
+
+    if (CheckSetup() == 1)
+        refreshAll = true;
+
+    if (config->refreshDisplay > 0)
+    {
+        refreshCounter = (refreshCounter + 1) % config->refreshDisplay;
+        if (!refreshAll && !refreshCounter)
+            refreshAll = true;
+    }
+
+    refreshAll = true;
+    if (refreshAll)
+    {
+        WriteCommand(kCmdSetColumnAddress, 0, width - 1);
+        WriteCommand(kCmdSetPageAddress, 0, numPages - 1);
+        for (x = 0; x < width; x++)
+        {
+            for (y = 0; y < numPages; y++)
+            {
+                data[y] = (newLCD[x][y]) ^ (config->invert ? 0xff : 0x00);
+            }
+            WriteData(data, numPages);
+            memcpy(oldLCD[x], newLCD[x], numPages);
+        }
+        // and reset RefreshCounter
+        refreshCounter = 0;
+    }
+    else
+    {
+        // draw only the changed bytes
+    }
+}
+
+void cDriverSSD1306::SetBrightness(unsigned int percent)
+{
+    WriteCommand(kCmdSetContrast, percent * 255 / 100);
+}
+
+void cDriverSSD1306::Reset()
+{
+    digitalWrite(kGpioReset, LOW);
+    usleep(1000);
+    digitalWrite(kGpioReset, HIGH);
+}
+
+void cDriverSSD1306::WriteCommand(uint8_t command)
+{
+    wiringPiSPIDataRW(kSpiBus, &command, 1);
+}
+
+void cDriverSSD1306::WriteCommand(uint8_t command, uint8_t argument)
+{
+    uint8_t buffer[2] = {command, argument};
+    wiringPiSPIDataRW(kSpiBus, buffer, 2);
+}
+
+void cDriverSSD1306::WriteCommand(uint8_t command, uint8_t argument1, uint8_t argument2)
+{
+    uint8_t buffer[3] = {command, argument1, argument2};
+    wiringPiSPIDataRW(kSpiBus, buffer, 3);
+}
+
+void cDriverSSD1306::WriteData(uint8_t * buffer, uint32_t length)
+{
+    digitalWrite(kGpioDC, HIGH);
+    wiringPiSPIDataRW(kSpiBus, buffer, length);
+    digitalWrite(kGpioDC, LOW);
+}
+
+} // end of namespace