--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/thermometers/lcd-pcf8574.c Sun May 25 22:06:56 2014 +0200
@@ -0,0 +1,142 @@
+/*
+ * lcd-pcf8574.c:
+ * Text-based LCD driver library code
+ * This is designed to drive the HD44780U LCD display connected via
+ * a "LCM1602 IIC A0 A1 A2" board with a PCF8574 I2C controller.
+ *
+ * Copyright (c) 2012-2013 Gordon Henderson.
+ * Copyright (c) 2014 Michiel Broek.
+ ***********************************************************************
+ *
+ * mbsePi is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * mbsePi is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with wiringPi. If not, see <http://www.gnu.org/licenses/>.
+ ***********************************************************************
+ */
+
+#include "thermometers.h"
+
+#ifdef HAVE_WIRINGPI_H
+
+int lcdHandle;
+unsigned char lcdbuf[MAX_LCDS][20][4];
+
+struct lcdDataStruct
+{
+ int bits, rows, cols ;
+ int rsPin, strbPin ;
+ int dataPins [8] ;
+ int cx, cy ;
+};
+extern struct lcdDataStruct *lcds [MAX_LCDS];
+
+
+/*
+ * Some LCD functions are extended shadow copies of the wiringPi functions.
+ * The difference is that the lcdbuf will be updated with the contents on
+ * the hardware display. This copy can then be used for a remote display
+ */
+
+
+/*
+ * setBacklight:
+ *********************************************************************************
+ */
+
+void setBacklight (int value)
+{
+ pinMode (AF_BACKLIGHT, OUTPUT) ;
+ digitalWrite (AF_BACKLIGHT, (value & 1)) ;
+}
+
+
+
+/*
+ * initLCD:
+ *********************************************************************************
+ */
+
+int initLCD (int cols, int rows)
+{
+ int x, y;
+
+ if (!((rows == 1) || (rows == 2) || (rows == 4))) {
+ fprintf (stderr, "rows must be 1, 2 or 4\n") ;
+ return EXIT_FAILURE ;
+ }
+
+ if (!((cols == 16) || (cols == 20))) {
+ fprintf (stderr, "cols must be 16 or 20\n") ;
+ return EXIT_FAILURE ;
+ }
+
+ pcf8574Setup(AF_BASE, 0x27) ;
+ pinMode (AF_RW, OUTPUT) ;
+ digitalWrite (AF_RW, LOW) ; // Not used with wiringPi - always in write mode
+
+ /*
+ * The other control pins are initialised with lcdInit ()
+ */
+ lcdHandle = lcdInit (rows, cols, 4, AF_RS, AF_E, AF_DB4, AF_DB5, AF_DB6, AF_DB7, 0, 0, 0, 0) ;
+ if (lcdHandle < 0) {
+ fprintf (stderr, "lcdInit failed\n") ;
+ return -1 ;
+ }
+
+ lcdClear (lcdHandle) ;
+ for (x = 0; x < 20; x++)
+ for (y = 0; y < 4; y++)
+ lcdbuf[lcdHandle][x][y] = ' ';
+
+ setBacklight (1) ;
+
+ return 0 ;
+}
+
+
+
+void mb_lcdPutchar(const int fd, unsigned char data)
+{
+ struct lcdDataStruct *lcd = lcds[fd];
+
+ /*
+ * Write to our buffer first, then to the wiringPi driver.
+ * Writing to wiringPi updates the cursor position.
+ */
+ lcdbuf[fd][lcd->cx][lcd->cy] = data;
+ lcdPutchar(fd, data);
+}
+
+
+
+void mb_lcdPuts(const int fd, const char *string)
+{
+ while (*string)
+ mb_lcdPutchar (fd, *string++);
+}
+
+
+
+void mb_lcdClear(const int fd)
+{
+ int x, y;
+
+ lcdClear(fd);
+ for (x = 0; x < 20; x++)
+ for (y = 0; y < 4; y++)
+ lcdbuf[fd][x][y] = ' ';
+}
+
+
+
+#endif
+