Mitsubishi DS907x SIP, DS5000TK manual Wbyte, 156

USER'S GUIDE

lcall	CLOSE		;Close date/time registers.
mov	IE,	#0
mov	TMOD,	#20H	;Initialize the
mov	TH1,	#0FAH	;serial port
mov	TL1,	#0FAH	;for 9600
orl	PCON,	#80H	;baud using 11.0592 MHz crystal.
mov	SCON,	#52H
mov	TCON,	#40H
L:
jnb	RI,	L	;Wait for character.
clr	RI		;Clear the receiver.
mov	A,	SBUF	;Load in the character.
cjne	A, #'R, H		;Skip if not a read.
lcall	OPEN		;Set up to read date/time.
mov	B	#8	;Set up to send 8 bytes.
F:
lcall	RBYTE		;Read a byte of date/time.
G:
jnb	TI,	G	;Wait for end of previous send.
clr	TI		;Clear transmitter.
mov	SBUF,	A	;Send out the byte.
djnz	B,	F	;Loop for 8 bytes.
sjmp	L		;Return to main loop.
H:
cjne	A, #'W', J		;Skip if not a write.
lcall	OPEN		;Set up to read date/time.
mov	B,	#8	; Set up to receive 8 bytes.
I:
jnb	RI,	I	;Wait to receive a byte.
clr	RI		;Clear the receiver.
mov	A,	SBUF	;Bring in the byte.
lcall	WBYTE		;Write a byte of date/time.
djnz	B,	I	;Loop for 8 bytes.
sjmp	L		;Return to main loop.
J:
jnb	TI,	J	;If it is neither an R nor a W
clr	TI		;increment the character,
inc	A		;send it back out to the
mov	SBUF,	A	;serial port, and then
sjmp	L		;return to the main loop.
;
;

;SUBROUTINE TO OPEN THE CLOCK/CALENDAR (ECC)

;This subroutine executes the sequence of reads and writes which

;is required in order to open communication with the timekeeper.

;The subroutine returns with the timekeeper opened for data

;access with both the accumulator and B register modified.

;

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