198 lines
5.8 KiB
NASM
198 lines
5.8 KiB
NASM
;------------------------------------------------------------------------------
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; iButton serial number reader
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; Addapter pour lire le 18b20 par http://adriy.be
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; http://avr-mcu.dxp.pl
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; e-mail: radek(at)dxp.pl
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; (c) Radoslaw Kwiecien
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;------------------------------------------------------------------------------
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;------------------------------------------------------------------------------
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; Defines
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;------------------------------------------------------------------------------
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#define F_CPU 16000000
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;Table 3. DS18B20 Function Command Set p12
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#define ReadRom 0x33
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#define SkipRom 0xcc
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#define ConvertTemp 0x44 ; Initiates temperature conversion.
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#define WScratch 0x4e ; Writes data into scratchpad bytes 2, 3, and4 (TH, TL, and configuration registers).
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#define RScratch 0xbe ; Reads the entire scratchpad including theCRC byte.
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;------------------------------------------------------------------------------
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; Data segment, variable definitions
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;------------------------------------------------------------------------------
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.dseg
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SerialNumber: .byte 8
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;------------------------------------------------------------------------------
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; Code segment
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;------------------------------------------------------------------------------
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.cseg
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;------------------------------------------------------------------------------
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; Include required files
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;------------------------------------------------------------------------------
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#include "vectors.asm"
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#include "hd44780.asm"
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#include "wait.asm"
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#include "1-wire.asm"
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#include "crc8.asm"
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;------------------------------------------------------------------------------
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; Constants definition
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;------------------------------------------------------------------------------
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Text1 :
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.db "iButton Reader",0,0
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Text2 :
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.db "avr-mcu.dxp.pl",0,0
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Tp :
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.db ".",0,0
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;------------------------------------------------------------------------------
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; Program entry point
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;------------------------------------------------------------------------------
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ProgramEntryPoint:
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ldi r16, LOW(RAMEND) ; Initialize stack pointer
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out SPL, r16 ;
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rcall LCD_Init ; Initialize LCD
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ldi r16, (HD44780_LINE0 + 1) ;
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rcall LCD_SetAddressDD ; Set Display Data address to (0,1)
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ldi ZL, LOW(Text1 << 1) ; Load string address to Z
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ldi ZH, HIGH(Text1<< 1) ;
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rcall LCD_WriteString ; Display string
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ldi r16, (HD44780_LINE1 + 1) ;
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rcall LCD_SetAddressDD ; Set Display Data address to (1,1);
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;ldi ZL, LOW(Text2 << 1) ;
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;ldi ZH, HIGH(Text2<< 1) ; Load string address to Z
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;rcall LCD_WriteString ; Display string
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ConfigResolTo10Bits:
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rcall OWReset
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brts ConfigResolTo10Bits
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ldi r16, SkipRom ; Write Skip Rom one wire in "single-drop"
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rcall OWWriteByte
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ldi r16, WScratch
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rcall OWWriteByte
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clr r16
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rcall OWWriteByte ;th,tl
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rcall OWWriteByte ;th,tl
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ldi r16, 63
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rcall OWWriteByte ;resol
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MainLoop:
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ldi r16, (HD44780_LINE1 + 1) ;
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rcall LCD_SetAddressDD ; Set Display Data address to (1,1);
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rcall OWReset ; One wire reset
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brts MainLoop ; If device not present go to MainLoop
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rcall TempRequest
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rcall MainReadTemp
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rcall ConvertTempForLCD
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;rcall CRC8Init ; Initialize CRC8 value
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jmp LoadLoop
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rcall OWReadByte ; Read first byte (Family ID)
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cpi r16,0 ; If first byte equal to zero, go to MainLoop
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breq MainLoop ; (short circuit on one wire bus)
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rcall CRC8Update ; Update the CRC
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ldi YL, LOW(SerialNumber) ;
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ldi YH, HIGH(SerialNumber) ; Load to Y address of SerialNumber table
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st Y+, r16 ; Store first byte to table, and increment pointer
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ldi r17, 7 ; 7 bytes remaining
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StoreLoop:
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rcall OWReadByte ; read next byte
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rcall CRC8Update ; update the CRC
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st Y+, r16 ; store next byte to table, and increment pointer
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dec r17 ; decrement loop counter
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brne StoreLoop ; if greater than zero, jump to StoreLoop
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rcall GetCRC8 ; Read computet CRC8
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cpi r16,0 ; copmare with zero
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brne MainLoop ; if not equal, jump to MainLoop (bad CRC)
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; else
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ldi r16, (HD44780_LINE1 + 0) ;
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rcall LCD_SetAddressDD ; Set DisplayData address to (0,1)
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ldi YL, LOW(SerialNumber) ;
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ldi YH, HIGH(SerialNumber) ; Load to Y address of SerialNumber table
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ldi r17,2 ; 8 digits to display
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LoadLoop:
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push r16
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mov r16, XL ; load to r16 byte from table
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push r16
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ldi r19,0xF0
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and r16,r19
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rcall bin2bcd8
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lsr r16
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lsr r16
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lsr r16
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lsr r16
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rcall LCD_WriteHexDigit ; display it on LCD in HEX
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pop r16
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rcall bin2bcd8
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ldi r18,0x0F
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and r16,r18
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rcall LCD_WriteHexDigit ; display it on LCD in HEX
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mov r16, r18 ; load to r16 byte from table
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push r16
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ldi r19,0xF0
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and r16,r19
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rcall bin2bcd8
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lsr r16
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lsr r16
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lsr r16
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lsr r16
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rcall LCD_WriteHexDigit ; display it on LCD in HEX
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pop r16
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rcall bin2bcd8
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ldi r18,0x0F
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and r16,r18
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rcall LCD_WriteHexDigit ; display it on LCD in HEX
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nop
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nop
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nop
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jmp MainLoop
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brne LoadLoop ; if not zero, jump to LoadLoop
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rjmp MainLoop ; jump to MainLoop
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;------------------------------------------------------------------------------
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; End of file
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;------------------------------------------------------------------------------
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;======= Converting from HEX to BCD ====================================================https://evileg.com/en/post/19/
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;*****************************************************
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;* "bin2BCD8" - 8-bit Binary to BCD conversion
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;* This subroutine converts an 8-bit number (temp) to a 2-digit
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;* i.e 0x15 becomes 0x21
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;* result in temp
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;**********************************************************
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;.def tBCD = r21 ;add this to main asm file
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;
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bin2bcd8:
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clr r21 ;clear temp reg
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bBCD8_1:
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subi r16,10 ;input = input - 10
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brcs bBCD8_2 ;abort if carry set
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subi r21,-$10 ;tBCD = tBCD + 10
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rjmp bBCD8_1 ;loop again
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bBCD8_2:
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subi r16,-10 ;compensate extra subtraction
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add r16,r21
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ret |