drivers/displays/character/samsung_20T202DA2JA/samsung_20T202DA2JA.c

   1 /**************************************************************************/
   2 /*!
   3     @file     samsung_20T202DA2JA.c
   4     @author   Original source : Limor Fried/ladyada (Adafruit Industries)
   5               LPC1343 port    : K. Townsend
   6
   7     @section DESCRIPTION
   8
   9     Driver for Samsung 20T202DA2JA 20x2 VFD display module.
  10
  11     This driver is based on the SPI_VFD Library from Limor Fried
  12     (Adafruit Industries) at: https://github.com/adafruit/SPI_VFD
  13
  14     The displays can be purchased at:
  15     https://www.adafruit.com/products/347
  16
  17     @section LICENSE
  18
  19     Software License Agreement (BSD License)
  20
  21     Copyright (c) 2012 Adafruit Industries
  22     All rights reserved.
  23
  24     Redistribution and use in source and binary forms, with or without
  25     modification, are permitted provided that the following conditions are met:
  26     1. Redistributions of source code must retain the above copyright
  27     notice, this list of conditions and the following disclaimer.
  28     2. Redistributions in binary form must reproduce the above copyright
  29     notice, this list of conditions and the following disclaimer in the
  30     documentation and/or other materials provided with the distribution.
  31     3. Neither the name of the copyright holders nor the
  32     names of its contributors may be used to endorse or promote products
  33     derived from this software without specific prior written permission.
  34
  35     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ''AS IS'' AND ANY
  36     EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  37     WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  38     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE FOR ANY
  39     DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  40     (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  41     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  42     ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  43     (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  44     SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  45 */
  46 /**************************************************************************/
  47 #include <string.h>
  48
  49 #include "samsung_20T202DA2JA.h"
  50
  51 #include "core/gpio/gpio.h"
  52 #include "core/systick/systick.h"
  53
  54 /**************************************************************************/
  55 /* Private Methods                                                        */
  56 /**************************************************************************/
  57
  58 uint8_t samsungvfd_displayfunction;
  59 uint8_t samsungvfd_displaycontrol;
  60 uint8_t samsungvfd_displaymode;
  61 uint8_t samsungvfd_initialized;
  62 uint8_t samsungvfd_numlines, samsungvfd_currline;
  63
  64 /**************************************************************************/
  65 /*!
  66     @brief Low-level SPI bit-banging routing
  67 */
  68 /**************************************************************************/
  69 static inline void samsungvfd_sendByte(uint8_t c) {
  70   int8_t i;
  71
  72   // Make sure clock pin starts high
  73   gpioSetValue(SAMSUNGVFD_SCK_PORT, SAMSUNGVFD_SCK_PIN, 1);
  74
  75   // Write from MSB to LSB
  76   for (i=7; i>=0; i--)
  77   {
  78     // Set clock pin low
  79     gpioSetValue(SAMSUNGVFD_SCK_PORT, SAMSUNGVFD_SCK_PIN, 0);
  80     // Set data pin high or low depending on the value of the current bit
  81     gpioSetValue(SAMSUNGVFD_SIO_PORT, SAMSUNGVFD_SIO_PIN, c & (1 << i) ? 1 : 0);
  82     // Set clock pin high
  83     gpioSetValue(SAMSUNGVFD_SCK_PORT, SAMSUNGVFD_SCK_PIN, 1);
  84   }
  85 }
  86
  87 /**************************************************************************/
  88 /*!
  89     @brief Sends a command to the VFD display
  90 */
  91 /**************************************************************************/
  92 void samsungvfd_command(uint8_t value)
  93 {
  94   gpioSetValue(SAMSUNGVFD_STB_PORT, SAMSUNGVFD_STB_PIN, 0);
  95   samsungvfd_sendByte(SAMSUNGVFD_SPICOMMAND);
  96   samsungvfd_sendByte(value);
  97   gpioSetValue(SAMSUNGVFD_STB_PORT, SAMSUNGVFD_STB_PIN, 1);
  98 }
  99
 100 /**************************************************************************/
 101 /*!
 102     @brief Initialises the VFD character display
 103 */
 104 /**************************************************************************/
 105 void samsungvfd_begin(uint8_t cols, uint8_t lines, uint8_t brightness)
 106 {
 107   // set number of lines
 108   if (lines > 1)
 109     samsungvfd_displayfunction = SAMSUNGVFD_2LINE;
 110   else
 111     samsungvfd_displayfunction = SAMSUNGVFD_1LINE;
 112
 113   if (brightness>SAMSUNGVFD_BRIGHTNESS25)       //catch bad values
 114     brightness = SAMSUNGVFD_BRIGHTNESS100;
 115
 116   // set the brightness and push the linecount with VFD_SETFUNCTION
 117   samsungvfdSetBrightness(brightness);
 118
 119   samsungvfd_numlines = lines;
 120   samsungvfd_currline = 0;
 121
 122   // Initialize to default text direction (for romance languages#include "SPI_VFD.h"
 123   samsungvfd_displaymode = SAMSUNGVFD_ENTRYLEFT | SAMSUNGVFD_ENTRYSHIFTDECREMENT;
 124   // set the entry mode
 125   samsungvfd_command(SAMSUNGVFD_ENTRYMODESET | samsungvfd_displaymode);
 126
 127   samsungvfd_command(SAMSUNGVFD_SETDDRAMADDR);  // go to address 0
 128
 129   // turn the display on with no cursor or blinking default
 130   samsungvfd_displaycontrol = SAMSUNGVFD_DISPLAYON;
 131   samsungvfdDisplay();
 132
 133   samsungvfdClear();
 134   samsungvfdHome();
 135 }
 136
 137 /**************************************************************************/
 138 /* Public Methods                                                         */
 139 /**************************************************************************/
 140
 141 /**************************************************************************/
 142 /*!
 143     @brief Initialises the VFD character display
 144 */
 145 /**************************************************************************/
 146 void samsungvfdInit(uint8_t brightness)
 147 {
 148   // Set all pins to output
 149   gpioSetDir(SAMSUNGVFD_SIO_PORT, SAMSUNGVFD_SIO_PIN, gpioDirection_Output);
 150   gpioSetDir(SAMSUNGVFD_STB_PORT, SAMSUNGVFD_STB_PIN, gpioDirection_Output);
 151   gpioSetDir(SAMSUNGVFD_SCK_PORT, SAMSUNGVFD_SCK_PIN, gpioDirection_Output);
 152
 153   // Set strobe and clock pins high by default
 154   gpioSetValue(SAMSUNGVFD_STB_PORT, SAMSUNGVFD_STB_PIN, 1);
 155   gpioSetValue(SAMSUNGVFD_SCK_PORT, SAMSUNGVFD_SCK_PIN, 1);
 156
 157   // Default to 2x20 display (SAMSUNG 20T202DA2JA)
 158   samsungvfd_begin(20, 2, brightness);
 159 }
 160
 161 /**************************************************************************/
 162 /*!
 163     @brief Writes a single character to the VFD display
 164 */
 165 /**************************************************************************/
 166 void samsungvfdWrite(uint8_t value)
 167 {
 168   gpioSetValue(SAMSUNGVFD_STB_PORT, SAMSUNGVFD_STB_PIN, 0);
 169   samsungvfd_sendByte(SAMSUNGVFD_SPIDATA);
 170   samsungvfd_sendByte(value);
 171   gpioSetValue(SAMSUNGVFD_STB_PORT, SAMSUNGVFD_STB_PIN, 1);
 172 }
 173
 174 /**************************************************************************/
 175 /*!
 176     @brief Writes a full string to the VFD display
 177 */
 178 /**************************************************************************/
 179 void samsungvfdWriteString(const char * str)
 180 {
 181   while(*str)
 182   {
 183     gpioSetValue(SAMSUNGVFD_STB_PORT, SAMSUNGVFD_STB_PIN, 0);
 184     samsungvfd_sendByte(SAMSUNGVFD_SPIDATA);
 185     samsungvfd_sendByte(*str++);
 186     gpioSetValue(SAMSUNGVFD_STB_PORT, SAMSUNGVFD_STB_PIN, 1);
 187   }
 188 }
 189
 190 /**************************************************************************/
 191 /*!
 192     @brief Sets the display brightness
 193 */
 194 /**************************************************************************/
 195 void samsungvfdSetBrightness(uint8_t brightness)
 196 {
 197   // set the brightness (only if a valid value is passed
 198   if (brightness <= SAMSUNGVFD_BRIGHTNESS25)
 199   {
 200     samsungvfd_displayfunction &= ~SAMSUNGVFD_BRIGHTNESS25;
 201     samsungvfd_displayfunction |= brightness;
 202
 203     samsungvfd_command(SAMSUNGVFD_FUNCTIONSET | samsungvfd_displayfunction);
 204   }
 205 }
 206
 207 /**************************************************************************/
 208 /*!
 209     @brief Quickly turn the display off
 210 */
 211 /**************************************************************************/
 212 void samsungvfdNoDisplay(void)
 213 {
 214   samsungvfd_displaycontrol &= ~SAMSUNGVFD_DISPLAYON;
 215   samsungvfd_command(SAMSUNGVFD_DISPLAYCONTROL | samsungvfd_displaycontrol);
 216 }
 217
 218 /**************************************************************************/
 219 /*!
 220     @brief Quickly turn the display on
 221 */
 222 /**************************************************************************/
 223 void samsungvfdDisplay(void)
 224 {
 225   samsungvfd_displaycontrol |= SAMSUNGVFD_DISPLAYON;
 226   samsungvfd_command(SAMSUNGVFD_DISPLAYCONTROL | samsungvfd_displaycontrol);
 227 }
 228
 229 /**************************************************************************/
 230 /*!
 231     @brief Turns the cursor off
 232 */
 233 /**************************************************************************/
 234 void samsungvfdNoCursor(void)
 235 {
 236   samsungvfd_displaycontrol &= ~SAMSUNGVFD_CURSORON;
 237   samsungvfd_command(SAMSUNGVFD_DISPLAYCONTROL | samsungvfd_displaycontrol);
 238 }
 239
 240 /**************************************************************************/
 241 /*!
 242     @brief Enables the cursor
 243 */
 244 /**************************************************************************/
 245 void samsungvfdCursor(void)
 246 {
 247   samsungvfd_displaycontrol |= SAMSUNGVFD_CURSORON;
 248   samsungvfd_command(SAMSUNGVFD_DISPLAYCONTROL | samsungvfd_displaycontrol);
 249 }
 250
 251 /**************************************************************************/
 252 /*!
 253     @brief Disable cursor blinking
 254 */
 255 /**************************************************************************/
 256 void samsungvfdNoBlink(void)
 257 {
 258   samsungvfd_displaycontrol &= ~SAMSUNGVFD_BLINKON;
 259   samsungvfd_command(SAMSUNGVFD_DISPLAYCONTROL | samsungvfd_displaycontrol);
 260 }
 261
 262 /**************************************************************************/
 263 /*!
 264     @brief Enable cursor blinking
 265 */
 266 /**************************************************************************/
 267 void samsungvfdBlink(void)
 268 {
 269   samsungvfd_displaycontrol |= SAMSUNGVFD_BLINKON;
 270   samsungvfd_command(SAMSUNGVFD_DISPLAYCONTROL | samsungvfd_displaycontrol);
 271 }
 272
 273 /**************************************************************************/
 274 /*!
 275     @brief Scroll the display left without changing the RAM
 276 */
 277 /**************************************************************************/
 278 void samsungvfdScrollDisplayLeft(void)
 279 {
 280   samsungvfd_command(SAMSUNGVFD_CURSORSHIFT | SAMSUNGVFD_DISPLAYMOVE | SAMSUNGVFD_MOVELEFT);
 281 }
 282
 283 /**************************************************************************/
 284 /*!
 285     @brief Scroll the display right without changing the RAM
 286 */
 287 /**************************************************************************/
 288 void samsungvfdScrollDisplayRight(void)
 289 {
 290   samsungvfd_command(SAMSUNGVFD_CURSORSHIFT | SAMSUNGVFD_DISPLAYMOVE | SAMSUNGVFD_MOVERIGHT);
 291 }
 292
 293 /**************************************************************************/
 294 /*!
 295     @brief Cause text to flow left to right
 296 */
 297 /**************************************************************************/
 298 void samsungvfdLeftToRight(void)
 299 {
 300   samsungvfd_displaymode |= SAMSUNGVFD_ENTRYLEFT;
 301   samsungvfd_command(SAMSUNGVFD_ENTRYMODESET | samsungvfd_displaymode);
 302 }
 303
 304 /**************************************************************************/
 305 /*!
 306     @brief Cause text to flow from right to left
 307 */
 308 /**************************************************************************/
 309 void samsungvfdRightToLeft(void)
 310 {
 311   samsungvfd_displaymode &= ~SAMSUNGVFD_ENTRYLEFT;
 312   samsungvfd_command(SAMSUNGVFD_ENTRYMODESET | samsungvfd_displaymode);
 313 }
 314
 315 /**************************************************************************/
 316 /*!
 317     @brief Right justify text from the cursor
 318 */
 319 /**************************************************************************/
 320 void samsungvfdAutoscroll(void)
 321 {
 322   samsungvfd_displaymode |= SAMSUNGVFD_ENTRYSHIFTINCREMENT;
 323   samsungvfd_command(SAMSUNGVFD_ENTRYMODESET | samsungvfd_displaymode);
 324 }
 325
 326 /**************************************************************************/
 327 /*!
 328     @brief Left justify text from the cursor
 329 */
 330 /**************************************************************************/
 331 void samsungvfdNoAutoscroll(void)
 332 {
 333   samsungvfd_displaymode &= ~SAMSUNGVFD_ENTRYSHIFTINCREMENT;
 334   samsungvfd_command(SAMSUNGVFD_ENTRYMODESET | samsungvfd_displaymode);
 335 }
 336
 337 /**************************************************************************/
 338 /*!
 339     @brief Clears the display
 340 */
 341 /**************************************************************************/
 342 void samsungvfdClear(void)
 343 {
 344   samsungvfd_command(SAMSUNGVFD_CLEARDISPLAY);  // clear display, set cursor position to zero
 345   systickDelay(2);                              // this command takes a long time!
 346 }
 347
 348 /**************************************************************************/
 349 /*!
 350     @brief Places the cursor at 0, 0
 351 */
 352 /**************************************************************************/
 353 void samsungvfdHome(void)
 354 {
 355   samsungvfd_command(SAMSUNGVFD_RETURNHOME);    // Set cursor position to zero
 356   systickDelay(2);                              // this command takes a long time!
 357 }
 358
 359 /**************************************************************************/
 360 /*!
 361     @brief Sets the cursor to the specified row and column position
 362 */
 363 /**************************************************************************/
 364 void samsungvfdSetCursor(uint8_t row, uint8_t col)
 365 {
 366   int row_offsets[] = { 0x00, 0x40, 0x14, 0x54 };
 367   if ( row > samsungvfd_numlines )
 368   {
 369     row = samsungvfd_numlines-1;                // we count rows starting w/0
 370   }
 371
 372   samsungvfd_command(SAMSUNGVFD_SETDDRAMADDR | (col + row_offsets[row]));
 373 }
 374