;********************************************************
;* 											  			*
;* 			RFM Transceiver Modul - Reciever			*
;*												 		*
;********************************************************
;Clock Speed 12 MHz

; I/O Zuweisung

		clock 		equ 	P1.1		
		data_out 	equ 	P1.0
		data_in		equ	   	P1.2
		chip_select	equ		P1.3

; Bytezuweisung

		input		bit		00h
		firstb		equ		21h
		secondb		equ		22h

;Startadresse des Programmes

		org 0000h
		ajmp main

;Timer Interrupt

		org 00Bh
		mov TH0,#03Ch			;Timer 0 High-Byte laden
		mov TL0,#0ABh			;Timer 0 Low-Byte laden
		inc a
		reti

;Hauptprogramm
		org 0100h
main:  	mov sp,#022h
		lcall init
		lcall delay
		lcall mod_init
wait:	lcall datain
		mov p3,a
		lcall delay
		lcall delay
		sjmp wait


; Initialisierung des Programm´s

init:	clr chip_select
		clr clock
		clr data_in
		clr a
		clr input
		mov r0,#0
		mov p3,#0ffh
		ret

; Warten auf Bereitschaft des Moduls

delay:		push acc
			mov TH0,#03Ch			;Timer 0 High-Byte laden
			mov TL0,#0AAh			;Timer 0 Low-Byte laden
			mov TMOD,#01h			;Timer 0 16-bit
			setb TR0				;Timer 0 starten
			mov IE,#082h			;Interrupt freigeben
			clr a
schleife:	cjne a,#4,schleife
			clr TR0
			mov IE,#0h
			pop acc
			ret

; Initialisierung des Moduls

mod_init:	mov firstb,#080h		;Configuration Setting	
			mov secondb,#0D7h  		
			lcall output
			mov firstb,#0C2h		;Data Filter Command	
			mov secondb,#0ABh
			lcall output
			mov firstb,#0CAh		;FIFO and Reset-Mode Command	
			mov secondb,#081h
			lcall output
			mov firstb,#0C4h		;AFC Command	
			mov secondb,#057h
			lcall output
			mov firstb,#0E0h	 	;Wake-Up Timer Command
			mov secondb,#000h
			lcall output
			mov firstb,#0C8h		;Low Duty-Cycle Command	
			mov secondb,#000h
			lcall output
			mov firstb,#0A6h		;Frequency Setting Command	
			mov secondb,#020h
			lcall output
			mov firstb,#090h	   	;Power Setting Command
			mov secondb,#08Ch  		
			lcall output
			mov firstb,#0C6h  		;Data Rate Command
			mov secondb,#091h
			lcall output
			mov firstb,#098h  		;Tx Configuration Control Command
			mov secondb,#073h
			lcall output
			ret


;Datenausgabe

output:		push acc
			push 0
			setb chip_select
			clr chip_select
			mov a,#080h
			mov r0,a
round1:		clr clock
			anl a,firstb
			clr data_out
			jz nset1
			setb data_out
nset1:		setb clock
			mov a,r0
			rr a
			mov r0,a
			cjne r0,#080h,round1
			jnb input,round2
			clr input
			pop 0
			pop acc
			ret

round2:		clr clock
			anl a,secondb
			clr data_out
			jz nset2
			setb data_out
nset2:		setb clock
			mov a,r0
			rr a
			mov r0,a
			cjne r0,#080h,round2
			pop 0
			pop acc
			ret

;Datenaufnahme

datain:		mov firstb,#082h  		;Power Management Command
			mov secondb,#0C8h		;Rx Enabled
			lcall output
			mov firstb,#0CAh  		;FIFO and Reset Mode Command
			mov secondb,#081h
			lcall output
			mov firstb,#0CAh  		;FIFO and Reset Mode Command
			mov secondb,#083h
			lcall output
			mov firstb,#0B0h		;Recieve Command
			setb input
			lcall output
			mov a,#0
			mov r0,#0
			clr data_out
in1:		rl a
			clr clock
			jnb data_in,in2
			add a,#1
in2:		inc r0
			setb clock
			cjne r0,#8,in1
			mov firstb,#082h  		;Power Management Command
			mov secondb,#008h		;Rx Disabled	
			lcall output
			ret
			

end