sys/dev/ic/hd44780reg.h

   1 /* $NetBSD: hd44780reg.h,v 1.3 2005/12/11 12:21:26 christos Exp $ */
   2
   3 /*
   4  * Copyright (c) 2002 Dennis I. Chernoivanov
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. The name of the author may not be used to endorse or promote products
  16  *    derived from this software without specific prior written permission
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28  */
  29
  30 #ifndef _DEV_IC_HD44780REG_H_
  31 #define _DEV_IC_HD44780REG_H_
  32
  33 /*
  34  * Register definitions for Hitachi HD44870 style displays
  35  */
  36
  37 #define HD_MAX_CHARS    80
  38
  39 #define HD_ROW1_ADDR    0x00
  40 #define HD_ROW2_ADDR    0x40
  41
  42 #define HD_TIMEOUT_LONG 5000
  43 #define HD_TIMEOUT_SHORT        100
  44 #define HD_TIMEOUT_NORMAL       200
  45
  46 #define BUSY_FLAG       0x80
  47
  48 /* Bit set helper */
  49 #define bset(cond, bit) ((cond) ? (bit) : 0x00)
  50
  51 /* Get 4 most/least significant bits */
  52 #define hi_bits(byte)   (((byte) & 0xf0) >> 4)
  53 #define lo_bits(byte)   ((byte) & 0x0f)
  54
  55 /*
  56  * 'Initialize by instruction'  8bit=1/0 8-bit/4-bit operation
  57  */
  58 #define cmd_init(mode)  ((uint8_t)(mode ? 0x3f : 0x03))
  59
  60 /*
  61  * 'Clear display'
  62  */
  63 #define cmd_clear()     ((uint8_t)0x01)
  64
  65 /*
  66  * 'Return home'
  67  */
  68 #define cmd_rethome()   ((uint8_t)0x03)
  69
  70 /*
  71  * 'Entry mode set'             id=1/0 increment/decrement
  72  *                              s=1  display shift
  73  */
  74 #define cmd_modset(id, s) \
  75         ((uint8_t)(0x04 | bset(id, 0x2) | bset(s, 0x1)))
  76
  77 /*
  78  * 'Display on/off control'     d=1/0 display on/off
  79  *                              c=1/0 cursor on/off
  80  *                              b=1/0 blinking of cursor position on/off
  81  */
  82 #define cmd_dispctl(d, c, b) \
  83         ((uint8_t)(0x08 | bset(d, 0x04) | bset(c, 0x02) | bset(b, 0x01)))
  84
  85 /*
  86  * 'Cursor or display shift'    sc=1/0 display shift/cursor move
  87  *                              rl=1/0 shift to the right/left
  88  */
  89 #define cmd_shift(sc, rl) \
  90         ((uint8_t)(0x13 | bset(sc, 0x08) | bset(rl, 0x04)))
  91
  92 /*
  93  * 'Function set'               dl=1/0 8 bits/4 bits operation
  94  *                              n=1/0  2 lines/1 line
  95  *                              f=1/0  5x10/5x8 dots font
  96  */
  97 #define cmd_funcset(dl, n, f) \
  98          ((uint8_t)(0x23 | bset(dl, 0x10) | bset(n, 0x08) | bset(f, 0x04)))
  99
 100 /*
 101  * 'Set CGRAM address'
 102  */
 103 #define cmd_cgramset(acg) \
 104         ((uint8_t)(0x40 | ((acg) & 0x3f)))
 105
 106 /*
 107  * 'Set DDRAM address'
 108  */
 109 #define cmd_ddramset(add) \
 110         ((uint8_t)(0x80 | ((add) & 0x7f)))
 111
 112 #endif /* _DEV_IC_HD44780REG_H_ */