/* Copyright (c) 2002, Marek Michalkiewicz Copyright (c) 2005, Bjoern Haase All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. * Neither the name of the copyright holders nor the names of contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ /* eeprom.S Contributors: Created by Marek Michalkiewicz eeprom_write_word and eeprom_write_block added by Artur Lipowski Complete rewrite using the original interface by Bjoern Haase . */ #include "macros.inc" #include "ctoasm.inc" #include "avr/io.h" #ifndef __EEPROM_REG_LOCATIONS__ /* 6-byte string denoting where to find the EEPROM registers in memory space. Adresses denoted in hex syntax with uppercase letters. Used by the EEPROM subroutines. First two letters: EECR address. Second two letters: EEDR address. Last two letters: EEAR address. */ #define __EEPROM_REG_LOCATIONS__ 1C1D1E #endif /* As long as we don't have a proper multilib environment: Let's make it possible to override the locations defined in the io headers. */ #ifdef EEPROM_REG_LOCATIONS_OVERRIDE #undef __EEPROM_REG_LOCATIONS__ #define __EEPROM_REG_LOCATIONS__ EEPROM_REG_LOCATIONS_OVERRIDE #define HEXNR CONCAT1(0x , EEPROM_REG_LOCATIONS_OVERRIDE) #ifdef EECR #undef EECR #define EECR _SFR_IO8((HEXNR >> 16) & 0xFF) #endif #ifdef EEDR #undef EEDR #define EEDR _SFR_IO8((HEXNR >> 8) & 0xFF ) #endif #ifdef EEAR #undef EEAR #define EEAR _SFR_IO8(HEXNR & 0xFF) #endif #ifdef EEARH #undef EEARH #endif #ifdef EEARL #undef EEARL #define EEARL EEAR #endif #endif #define _EELABEL(x) CONCAT1(__,CONCAT1(x, CONCAT1 (_,__EEPROM_REG_LOCATIONS__))) /* the same library is used for 2313 and 8515 for now - I hope writing 0 to non-existent EEARH doesn't hurt... */ #ifndef EEARH #define EEARH (EEARL+1) #endif #ifdef L_eeprom_read_byte /* read one byte from EEPROM. addr = r26:r27, result = __tmp_reg__ Post increment r26:r27. */ .section .text.eeprom, "ax", @progbits .global _EELABEL(eeprom_read_byte) _EELABEL(eeprom_read_byte): sbic _SFR_IO_ADDR(EECR), EEWE rjmp _EELABEL(eeprom_read_byte) /* make sure EEPROM is ready */ #ifdef EEARH out _SFR_IO_ADDR(EEARH),r27 #endif out _SFR_IO_ADDR(EEARL),r26 sbi _SFR_IO_ADDR(EECR), EERE adiw r26,1 /* Increment x register */ in __tmp_reg__, _SFR_IO_ADDR(EEDR) ret #endif /* L_eeprom_read_byte */ #ifdef L_eeprom_read_word /* read one word from EEPROM. addr = r26:r27, result = r30:r31 Post increment r26:r27. */ .section .text.eeprom, "ax", @progbits .global _EELABEL(eeprom_read_word) _EELABEL(eeprom_read_word): rcall _EELABEL(eeprom_read_byte) mov r30,__tmp_reg__ rcall _EELABEL(eeprom_read_byte) mov r31,__tmp_reg__ ret #endif #ifdef L_eeprom_write_byte /* write a byte to EEPROM Address in r26:r27, value in __tmp_reg__ Post increment r26:r27. */ .section .text.eeprom, "ax", @progbits .global _EELABEL(eeprom_write_byte) _EELABEL(eeprom_write_byte): sbic _SFR_IO_ADDR(EECR), EEWE rjmp _EELABEL(eeprom_write_byte) /* make sure EEPROM is ready */ #ifdef EEARH out _SFR_IO_ADDR(EEARH), r27 #endif out _SFR_IO_ADDR(EEARL), r26 out _SFR_IO_ADDR(EEDR),__tmp_reg__ adiw r26,1 /* Increment x register */ in __tmp_reg__, _SFR_IO_ADDR(SREG) cli ; /* no ints between setting EEMWE and EEWE */ sbi _SFR_IO_ADDR(EECR), EEMWE sbi _SFR_IO_ADDR(EECR), EEWE out _SFR_IO_ADDR(SREG), __tmp_reg__ ret #undef val #endif /* L_eeprom_write_byte */ #ifdef L_eeprom_write_word /* write a word to EEPROM Address in r26:r27, value in __tmp_reg__ (LSB) and __zero_reg__ (MSB) Post increment r26:r27. */ .section .text.eeprom, "ax", @progbits .global _EELABEL(eeprom_write_word) _EELABEL(eeprom_write_word): rcall _EELABEL(eeprom_write_byte) mov __tmp_reg__,__zero_reg__ rcall _EELABEL(eeprom_write_byte) clr __zero_reg__ ret #endif #ifdef L_eeprom_read_block /* read a block of n (maximum 256) bytes from EEPROM ram_buffer = r30:r31, eeprom_addr = r26:r27, n = __zero_reg__ an initial value of 0 in __zero_reg__ corresponds to a value of n == 256. */ .section .text.eeprom, "ax", @progbits .global _EELABEL(eeprom_read_block) .global _EELABEL(eeprom_read_byte) _EELABEL(eeprom_read_block): rcall _EELABEL(eeprom_read_byte) st z+,__tmp_reg__ dec __zero_reg__ brne _EELABEL(eeprom_read_block) ret #endif /* L_eeprom_read_block */ #ifdef L_eeprom_write_block /* Write a block of n (maximum 256) bytes to EEPROM ram_pointer = r30:r31, eeprom_addr = r26:r27, n = __zero_reg__ an initial value of 0 in __zero_reg__ correspond to a value of n == 256. */ .section .text.eeprom, "ax", @progbits .global _EELABEL(eeprom_write_block) .global _EELABEL(eeprom_write_byte) _EELABEL(eeprom_write_block): ld __tmp_reg__,z+ rcall _EELABEL(eeprom_write_byte) dec __zero_reg__ brne _EELABEL(eeprom_write_block) ret #endif /* L_eeprom_write_block */ .end