Nokia lcd include , small footprint to suit pic16's

[Mike, K8LH]

Yes, I already thought about using the SPI module. The current bit-bang driver uses 14 words of memory and runs at ~190-kb/s (with 8-MHz clock). An SPI driver and its init code shouldn't be any bigger. I hope to work on an SPI driver later today. I just need to refresh my memory on the SPI modes. Looks like you're using CKE = 1 and CKP = 0, yes?



Implementing the 'packed' font table and extracting data was surprisingly simple, though I'm coding pretty close to the metal and the results are nothing as agile or elegant as your use of the 'readcode' function. Here's an excerpt, if you're interested;

  /********************************************************************
   *                                                                  *
   ********************************************************************/
   void RdFlash()               // bank 3 (inserted by compiler)
   { asm bcf     _eecon1,CFGS   // not 'config' memory            |03
     asm bsf     _eecon1,EEPGD  // select 'program' memory        |03
     asm bsf     _eecon1,RD     // initiate read operation        |03
     asm nop                    // required nop                   |03
     asm nop                    //  "                             |03
     asm incf    _eeadrl,F      // bump EEADR                     |03
     asm btfsc   _status,Z      //  "                             |03
     asm incf    _eeadrh,F      //  "                             |03
     asm rlf     _eedatl,W      // move b7 into Carry             |03
     asm rlf     _eedath,W      // wreg = the 7 bit hi byte       |03
     asm bcf     _eedatl,7      // eedatl = the 7 bit lo byte     |03
   }                            //

  /********************************************************************
   *                                                                  *
   ********************************************************************/
   void WrChar(char ascii)      // WrChar() for packed 5x7 font
   { asm movf    _ascii,W       // ascii char value, 32..127      |00
     asm addlw   -32            // minus table offset             |00
     asm movwf   _ascii         // font array index, 0..95        |00
 /*                                                                   *
  *  multiply index by 3 (0..95 -> 0..285), add table base address,   *
  *  and stuff the result in the EEADR register pair.                 *
  *                                                                   */
     asm lslf    _wreg,W        // wreg = (ascii-32)*2            |00
     asm addwf   _ascii,W       // wreg = (ascii-32)*3            |00
  // asm movlb   3              // bank 3 (inserted by compiler)  |03
     asm movwf   _eeadrl        // flash address lo               |03
     asm movlw   1024/256       // table address hi               |03
     asm btfsc   _status,C      // overflow? no, skip, else       |03
     asm addlw   1              // bump value                     |03
     asm movwf   _eeadrh        // flash address hi               |03
 /*                                                                   *
  *  read 3 words (6 bytes) of font pattern data from the 5x7 font    *
  *  array and write them to the Nokia 5110 LCD.                      *
  *                                                                   */
     for(char i=0; i<3; i++)    // 
     { RdFlash();               // read one word (2 bytes)
       putlcd(wreg);            // send hi byte
       putlcd(eedatl);          // send lo byte
     }                          //
   }                            //

  /********************************************************************
   *                                                                  *
   ********************************************************************/
   void WrChar(rom char *data)  // overload function for strings
   { char ndx = 0;              //
     while(data[ndx++])         // while not end-of-string
       WrChar(wreg);            //
   }                            //

 /*                                                                   *
  *  initialize Nokia 5110 LCD display                                *
  *                                                                   */
     delay_ms(30);              //
     rst = 0;                   // 5110 'reset' pulse
     rst = 1;                   //
     dc = 0;                    // command mode
     putlcd(0x20+0x01);         // function set: extended instructions
     putlcd(0x80+0x30);         // set Vop (contrast), 0..127
     putlcd(0x04+0x02);         // set temperature coefficient, 0..3
     putlcd(0x10+0x03);         // Set bias system, 0..7
     putlcd(0x20+0x00);         // function set: standard instructions
     putlcd(0x08+0x04);         // display control: normal mode

     putlcd(0x80+0x20);         // set DDRAM X address, 0..83
     putlcd(0x40+0x02);         // set DDRAM Y address, 0..5
     dc = 1;                    // data mode
     WrChar("Hello");           // test string overload function

Thank you again for sharing your work. Mike