common/cmd_display.c

   1 /*
   2  * (C) Copyright 2005
   3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   4  *
   5  * See file CREDITS for list of people who contributed to this
   6  * project.
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation; either version 2 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  21  * MA 02111-1307 USA
  22  */
  23
  24 #include <common.h>
  25 #include <command.h>
  26
  27 #undef DEBUG_DISP
  28
  29 #define DISP_SIZE       8
  30 #define CWORD_CLEAR     0x80
  31 #define CLEAR_DELAY     (110 * 2)
  32
  33 int do_display (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
  34 {
  35         int i;
  36         int pos;
  37
  38         /* Clear display */
  39         *((volatile char*)(CONFIG_SYS_DISP_CWORD)) = CWORD_CLEAR;
  40         udelay(1000 * CLEAR_DELAY);
  41
  42         if (argc < 2)
  43                 return (0);
  44
  45         for (pos = 0, i = 1; i < argc && pos < DISP_SIZE; i++) {
  46                 char *p = argv[i], c;
  47
  48                 if (i > 1) {
  49                         *((volatile uchar *) (CONFIG_SYS_DISP_CHR_RAM + pos++)) = ' ';
  50 #ifdef DEBUG_DISP
  51                         putc(' ');
  52 #endif
  53                 }
  54
  55                 while ((c = *p++) != '\0' && pos < DISP_SIZE) {
  56                         *((volatile uchar *) (CONFIG_SYS_DISP_CHR_RAM + pos++)) = c;
  57 #ifdef DEBUG_DISP
  58                         putc(c);
  59 #endif
  60                 }
  61         }
  62
  63 #ifdef DEBUG_DISP
  64         putc('\n');
  65 #endif
  66
  67         return (0);
  68 }
  69
  70 /***************************************************/
  71
  72 U_BOOT_CMD(
  73         display,        CONFIG_SYS_MAXARGS,     1,      do_display,
  74         "display string on dot matrix display",
  75         "[<string>]\n"
  76         "    - with <string> argument: display <string> on dot matrix display\n"
  77         "    - without arguments: clear dot matrix display\n"
  78 );