WScratch equ? H'0F'? ; 0x0f + Addr + data + data + .+ reset pulse
??????? ; // [Master --> ScratchPad ]
RScratch equ? H'AA'? ; 0xaa + Addr + R + R +.. + reset pulse
??????? ; // [ScratchPad --> Master ]
CPScratch equ? H'55'? ; 0x55 + 0xa5 + hi 10ms?? // [ScratchPad --> EEPROM ]
REEROM? equ? H'F0'? ; 0xf0 + Addr +R +R + reset pulse
??????? ; // [EEPROM(addr) --> ScratchPad]
??????? ; 0xf0 + reset pulse? // [EEPROM --> ScratchPad]

;; application register , application register is OTP, there are 7 bytes
;; pay attention when you use application register , it's a 64 bit OTP
WApR? equ? H'99'? ; 0x99 + Addr + data + data .. + reset pulse
??????? ; [Master? --> Application Reg]
RStatus? equ? H'66'? ; 0x66 + 0x00 + status + reset pulse

RApR? equ? H'C3'? ; 0xc3 + addr + data + .. + reset pulse
??????? ; application register --> master? ( locked)
??????? ; register scratchpad? --> master? ( not lock)
LockAp? equ? H'5A'? ; 0x5A + 0xa5
??????? ; [ register scratchpad --> application register]
??????? ; 0x5A + reset pulse cancel copy command
??????? ; a OTP type do once only
?????
?????
AppLocked equ? B'11111100' ; application locked, the value is data in the status
???????
???????

;; ROM function command// implement skip rom only

SkipROM? equ? H'CC' ;access memory directly
SerachROM equ? H'f0' ;read a bit , read the complement of the bit,write bit
MatchROM equ? H'55' ;0x55 + 64 bit rom bit??
ReadROM? equ? H'33' ;[family code & serial number & CRC ==> master ]
?
?? org?? H'00'
?? nop
?? goto main
??
;;ISR? **
?? org? H'04'
?? goto isr??
isr
?? movwf W_SAVE??? ;; W_SAVE=W
?? swapf STATUS,W?? ;;
?? movwf STATUS_SAVE?? ;; STATUS_SAVE=STATUS[3:0]& STATUS[7:4]
?? btfss PIR1,TMR1IF?? ;; TMR1IF
?? goto exit_int_source_check
????????? ;; timer 1 service?????????
?? nop
?? nop
?? nop
?? nop
?????????
?????????
exit_int_source_check???? ;; restore STATUS & W before exit from
?? swapf STATUS_SAVE,W? ;; W=STATUS_SAVE=STATUS[3:0]& STATUS[7:4]
?? movwf STATUS????
?? swapf W_SAVE,F?? ;; restore W
?? swapf W_SAVE,W?????????
?? retfie
;; ISR?? &&&??
main?????????
?
? call init
? call init_int_en

? movlw H'21'
? movwf FSR
? movlw H'3c'
? movwf INDF???? ;
;-----------------------------------------------?
;---------? read test --------------------------?
;-----------------------------------------------
;? movlw H'00'
;? banksel Addr
;? movwf Addr
;? call RdDS2430
?
;? movlw H'01'
;? banksel Addr
;? movwf Addr
;? call RdDS2430
;?
;? movlw H'02'
;? banksel Addr
;? movwf Addr
;? call RdDS2430
;------------------------------------------------?
;? banksel Offset
;? clrf Offset
;? pagesel VendorTable
;? call VendorTable
;? movwf Temp
;?
;
?
? movlw H'00'
? banksel Addr
? movwf Addr?
? movlw H'34'
? banksel TxBuffer
? movwf TxBuffer
? call WrDS2430
?
? movlw H'01'
? banksel Addr
? movwf Addr
? movlw H'35'?
? banksel TxBuffer
? movwf TxBuffer
? call WrDS2430?
?
? movlw H'02'
? banksel Addr
? movwf Addr
? movlw H'36'
? banksel TxBuffer
? movwf TxBuffer
? call WrDS2430?
?
???
;-------- read address 0 --------------------------?
? movlw H'00'
? movwf Addr
? call RdDS2430
?
? goto $????
;----------------------------------------------
; template to init before write
; to DS2430
;-----------------------------------------------?
;? movlw H'00'
;? movwf Addr?
;? movlw H'3C'
;? movwf TxBuffer?
?
;---------------------------------------------
; write DS2430 one byte
; input
; Addr = starting address to write
; TxB? = data to save
; output =
; ErrCode = 0 -> write ok
;?? = 1 -> write fail
;-----------------------------------------------
WrDS2430?
? call WrScratchPAD
? call CP2EE
? return

;------------------------------------------------
; template to init before read
; to DS2430
;-------------------------------------------------?
;?? movlw H'00'
;? movwf Addr??

;-------------------------------------------------
; read DS2430 one byte
; input
; Addr = starting address to read
; output
; RxB? = data to read
;--------------------------------------------------
RdDS2430
? call REE2ScratchPAD?
? call HostRdScratchPAD
? return

;;---------? host read scratch pad ----------------------------
;; save desired data into RxB
;;
;;--------------------------------------------------------------
?
HostRdScratchPAD
? call? DS2430AInitState
? banksel TxB
? movlw SkipROM
? movwf TxB?
? call? TxBYTE??? ; SkipROM
?
? movlw RScratch?? ; read scratch PAD Command
? movwf TxB
? call TxBYTE
?
? movf Addr,W??? ; starting address to read
? movwf TxB
? call TxBYTE
???
? call R2430A??? ; read desired scratch pad into RxB
? call??? RstPulse
? return
?
?
;-------------- write memory scratch scratch pad ------------------------
; write one byte into scratch PAD
; input
; Addr?? = starting address to write
; TxBuffer = data to save
; output
; ErrCode = 0 -> write ok
;?? = 1 -> write fail
;---------------------------------------------------------------------------

WrScratchPAD
? call DS2430AInitState
? movlw SkipROM??? ; 0xCC
? movwf TxB
? call? TxBYTE??? ; SkipROM
?
? movlw WScratch?? ; write memory scratch pad, 0x0f
? movwf TxB
? call TxBYTE
?
? movf Addr,W??? ; starting address of memory scratch pad
? movwf TxB???? ; TxBYTE use TxB
? call TxBYTE
?
? movf TxBuffer,W?? ;
? movwf TxB
? call TxBYTE???
? call RstPulse?? ; reset pulse
? call delay500us?? ; wait presence pulse???
? return?
?
;---------- CP2EE ---copy whole scratch pad to EE ----------------------
;? write memory scratch
;? verify memory scratch
;? copy memory scratch to EE
;----------------------------------------------------------------------
CP2EE
? call? DS2430AInitState ; 0x55 + 0xa5 + hi 10ms // [ScratchPad -> EEPROM ]?
? banksel TxB
? movlw SkipROM
? movwf TxB?
? call? TxBYTE??? ; SkipROM
? movlw CPScratch?? ; 0x55
? movwf TxB
? call TxBYTE
? movlw H'a5'
? movwf TxB
? call TxBYTE
? call ForceHi??? ; min 10ms refter to datasheet
? return

;--------- REE2ScratchPAD --- copy whole EE to ScrathPAD ----------------
;? copy EE to whole memory scatch
;? read memory scratch
;format I:? 0xf0 + Addr +R +R + reset pulse, copy byte by byte
;format II:? 0xf0 + Addr + reset pulse, copy whole
;------------------------------------------------------------------------
REE2ScratchPAD
? call? DS2430AInitState
? banksel TxB
? movlw SkipROM
? movwf TxB?
? call? TxBYTE??? ; SkipROM
? movlw REEROM??? ;; Read from EE into ScratchPAD
? movwf TxB
? call TxBYTE??? ;;
? call??? RstPulse?? ;; copy all
? return
?
;----------R2430A ---- Host read the scratch PAD ------------------------
; Read 2430A Scratch PAD
; LSB first
;?? save the result in RxB
;------------------------------------------------------------------------

R2430A?????????????? ; returns byte in RxB
? movlw .8
? movwf LoopCounter
??????? clrf RxB
RLoop
? call? SetLo?? ;
??????? nop
? call? SetHi?? ; it will pull up by resistor
? nop????? ; delay to sample reliable bit
? nop
? nop
? nop
? nop
? nop
? nop
? nop
? nop
? nop
? nop?
??????? nop
??????? nop
??????? nop
??????? nop
???????
??????? banksel PORTB
??????? movf PORTB,W
??????? movwf Temp
??????? btfss Temp,Bit2

? goto gLo
? bsf? CARRY
? goto rol
gLo?
? bcf? CARRY
rol?
? banksel RxB
??????? rrf? RxB,F
??????? call delay60us? ; tdrv + trelease
??????? banksel LoopCounter
??????? decfsz LoopCounter,F
??????? goto RLoop
??????? movf RxB,W?? ; save the result in W
??????? return
??
;----------------------------------------------------------
; strong pull up
;
;----------------------------------------------------------
ForceHi

? bsf? PBDir,Bit2
? movf PBDir,W?? ;; input

? banksel TRISB
? movwf TRISB?? ;; set input, pull by external resistor
? call delay100ms
? bcf? PBDir,Bit2? ;; output
? movf PBDir,W
? movwf TRISB
??????? return
;-------------------------------------------------------------
; reset pulse
;
;--------------------------------------------------------------
RstPulse
? call SetHi
? call SetLo
? call delay500us
? call??? SetHi?? ;Pull up by resistor
? return
;---------------------------------------------------------------
; reset pulse followed presence pulse
;
;---------------------------------------------------------------
DS2430AInitState
??????? call SetHi
??????? call SetLo
??????? call delay500us?? ; reset pulse
? call SetHi
? call delay500us?? ; presence pulse, pull up by resistor
? return

;-----------------------------------------------------------------------
??
init
?movlw H'3f'
?movwf PBDir?? ; 0x00111111
?banksel TRISB
?movwf TRISB?? ; force all portC as input
; movlw b'00000000'? ; GP2 pull-up,GP4 output
; movwf WPU??? ; connect the D of DS2430A to Port A
;--------------------------------------------------------------------
;? toggle from bank0 to bank1
;?? option register
;?? 7:? 1: port A pull-up OFF, 0:port A pull-up ON
;?? 6:? 1: rising INT , 0:fall INT
;?? 5:? 1: T0CKI to TMR0, 0: internal cycle to TMR0
; 4:? 1: Hi to Lo count 0: Lo to Hi count
; 3:? 1: Precale to WDT 0: Prescale to TMR0
;?? 2:0 prescale value
;---------------------------------------------------------------------?
?movlw b'11000010'? ;; pull-up ON,rising INT, internal cycle to TMR0,Lo to Hi count,Pre to TMR0,1:8
?movwf OPTION_REG? ;; ,prescal over 8
?banksel INTCON
?clrf INTCON
?clrf PORTB
?movlw 0x07?? ;; comparator off
?movwf CMCON?? ;; comparator off
?clrf TMR0

;;--------------------------------------------------------
;; 7: X
;; 6:??? 1: Timer1 on if T1G\
;; 5:4?? : 11:/8,10:/4,01:/2,00:/1
;;? 3 :?? 1 LP for timer 1 on, 0: LP for timer1 of
;;? 2 :?? 1 do not sync external , 0 sync external clock
;; 1 :?? 1: clock source external , 0: clock source internal??
;; 0 :?? 1: enable timer 1 ,0: disable timer 1
;;---------------------------------------------------------
?
; movlw b'00000000'? ;x,no gate control,over 8,LP osc to timer1 off,x,internal clock,stop timer
; movwf T1CON
?movlw b'00111000'
?movwf T1CON
?clrf PIR1
?return
?
;;-------------------------
;; init interrup enable,
;;-------------------------
init_int_en?

?banksel INTCON
?bsf INTCON,GIE?? ;; GIE=1
?bcf INTCON,PEIE?? ;;
?bcf INTCON,T0IE?? ;; T0IE=1
?bcf INTCON,INTE?? ;; GP2 interrupt enable
; bcf INTCON,RAIE?? ;; disable GPIO port change interrupt

;------------------------------------------------
; clear int flag
;------------------------------------------------
?bcf INTCON,T0IF
?bcf INTCON,INTF
; bcf INTCON,RAIF
?bcf PIR1,TMR1IF?
; movlw H'00'
; movwf INTCON

?banksel PIE1
?bcf PIE1,EEIE
?bcf PIE1,ADIE
?bcf PIE1,CMIE
?bsf PIE1,TMR1IE?? ; enable Timer 1, timer 1 use as delay
?return
??
;--------------------------------------------
; Tx BYTE to 2430A
; LSB first, MSB last
;--------------------------------------------
TxBYTE
?movlw .8
??? movwf LoopCounter
??? bcf? CARRY
RollTxB
?banksel TxB
?rrf? TxB,F
?btfss CARRY
?goto LoBit
?call TxHi
?goto bloop
LoBit
?call TxLo
bloop
?banksel LoopCounter
?decfsz LoopCounter,F
?goto RollTxB
??? return

;;---------------------------------------------------------
TxL
?call SetLo
?call delay60us?? ; min 60 us
??? call SetHi
??? nop?????? ; recovery time min 1us
??? nop?
??? return
;-----------------------------------------------------------
; tx hi
;-----------------------------------------------------------

TxHi:
?call SetLo??? ;1us?nop
?call SetHi
??? call delay60us
??? nop
??? nop?????? ;recovery time min 1us
?return

;;---------------------------------------------------------------------------
;;? toggle the RC0 as input and the bus was pulled up by externl resistor
;;? application default PCDir.Bit0 to output
;;---------------------------------------------------------------------------
SetHi:
? bsf? PBDir,Bit2
? movf PBDir,w
;? bsf? bank1
? banksel TRISB
? movwf TRISB
? return
;;----------------------------------------------------------------------------
;;? clear register file RC0
;;----------------------------------------------------------------------------

SetL
? banksel PORTB
? bcf? PORTB,Bit2? ; data lo
? bcf? PBDir,Bit2? ; direction out
? movf PBDir,W
? banksel TRISB
? movwf TRISB???????
??????? return
???????
;---------------------------
; fix delay 60 us
; 0xffff - 8 = 0xfff7
;---------------------------
delay60us
?banksel PIR1
?bcf? PIR1,TMR1IF
?movlw H'EE'
?movwf TMR1L
?movlw H'FF'
?movwf TMR1H
?bsf? T1CON,TMR1ON
?btfss PIR1,TMR1IF
?goto $-1
?bcf? T1CON,TMR1ON
?bcf? PIR1,TMR1IF
?return

;---------------------------
; fix delay 500 us
; 0xffff - 0x3e = 0xffc1
;---------------------------
delay500us