bootloader/rs232.c

   1 /*
   2     e07 bootloader suite
   3     Copyright (c) 2008 Daniel Mack <daniel@caiaq.de>
   4
   5     This program is free software: you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation, either version 3 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14
  15     You should have received a copy of the GNU General Public License
  16     along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17 */
  18
  19 #include "regs.h"
  20 #include "types.h"
  21 #include "wikireader.h"
  22
  23 enum {
  24         SPI_WRITE = 0,
  25         SPI_READ = 1,
  26         SPI_CS_HI = 2,
  27         SPI_CS_LO = 3
  28 };
  29
  30 int main(void)
  31 {
  32         u8 cmd, dat, len;
  33
  34         init_pins();
  35         init_rs232_ch0();
  36         SDCARD_CS_HI();
  37         EEPROM_CS_HI();
  38
  39         /* EEPROM WP: off */
  40         EEPROM_WP_HI();
  41
  42         /* enable SPI: master mode, no DMA, 8 bit transfers */
  43         REG_SPI_CTL1 = 0x73 | (7 << 10) | (7 << 4);
  44
  45         for (;;) {
  46                 do {} while (!(REG_EFSIF0_STATUS & 0x1));
  47                 cmd = REG_EFSIF0_RXD;
  48
  49                 switch (cmd) {
  50                         case SPI_CS_HI:
  51                                 EEPROM_CS_HI();
  52                                 break;
  53                         case SPI_CS_LO:
  54                                 EEPROM_CS_LO();
  55                                 break;
  56                         case SPI_WRITE:
  57                                 do {} while (!(REG_EFSIF0_STATUS & 0x1));
  58                                 len = REG_EFSIF0_RXD;
  59
  60                                 while (len--) {
  61                                         do {} while (!(REG_EFSIF0_STATUS & 0x1));
  62                                         dat = REG_EFSIF0_RXD;
  63                                         REG_SPI_TXD = dat;
  64                                         do {} while (REG_SPI_STAT & (1 << 6));
  65                                 }
  66                                 break;
  67                         case SPI_READ:
  68                                 do {} while (!(REG_EFSIF0_STATUS & 0x1));
  69                                 len = REG_EFSIF0_RXD;
  70
  71                                 while (len--) {
  72                                         REG_SPI_TXD = 0x00;
  73                                         do {} while (REG_SPI_STAT & (1 << 6));
  74                                         dat = REG_SPI_RXD;
  75                                         REG_EFSIF0_TXD = dat;
  76                                         do {} while (REG_EFSIF0_STATUS & (1 << 5));
  77                                 }
  78                                 break;
  79                 }
  80         }
  81 }
  82