softus.asm

Software UART asm code for microchip

; XTAL : 16 MHz
; PIC16F877
; DS18B20
;---------------------------------------
	LIST 	P = 16F877, R = HEX
	INCLUDE	"P16F877.INC"
;---------------------------------------
	ORG		0X00
	GOTO	START		
;	ORG		0X04
;	GOTO	ISR
;---------------------------------------
	#DEFINE	DSPIN	PORTB, 0
	#DEFINE	TXPIN	PORTB, 1
	#DEFINE RXPIN	PORTB, 2		
;---------------------------------------
DELAY1	EQU	0X20
TEMP1	EQU	0X21
TEMP2	EQU	0X21
KOMUT	EQU	0X22
DELAY2	EQU	0X23
DELAY3	EQU	0X24
SAYAC	EQU	0X25
BTX		EQU	0X26
BRX		EQU	0X27
SAYAC1	EQU	0X28
;---------------------------------------
; KATSAYI = (((1/istenilen Baundrate)/(KCS)-5)/4)
; KCS --> 4X(1/XTAL)
;  9600 baundrate 4   Mhz KATSAYI --> KATSAYI = 25   
;  9600 baundrate 8   Mhz KATSAYI --> KATSAYI = 50
;  9600 baundrate 16  Mhz KATSAYI --> KATSAYI = 103   
; (4XKATSAYI + 5
		;-------------------------------
DELAYSU MACRO	KATSAYI		; DELAYSU macrosu
	MOVLW	KATSAYI			; W = KATSAYI
	CALL	DELAY_2			; DELAY_2 ui 鏰瘕r
	ENDM					; Macroyu sonland齬.
;---------------------------------------
DELAY_2: 					; 2 祍
	MOVWF	DELAY3			; 1 礢	
	NOP						; DELAY3
	DECFSZ	DELAY3			; DELAY3 + 1 祍
	GOTO	$ - 2			; 2XDELAY3
	RETURN					; 2 祍	
;---------------------------------------
TXLOAD	MACRO
	BSF		STATUS, 5
	BCF		TRISB,	1
	BCF		STATUS, 5
	ENDM
;---------------------------------------
RXLOAD	MACRO
	BSF		STATUS, 5
	BSF		TRISB, 	2
	BCF		STATUS,	5
	CLRF	BRX
	ENDM
;---------------------------------------
TX:							; G鰊derim altyordam