******************************************************************************
* Program from page 4-27 in the 68HC11 EVB eval manual
******************************************************************************

* denote all numbers with hex radix using $ prefix
* labels included for readability

	ORG  $C000	* set origin of program 

        LDY #$C200	* first byte where data is stored
        LDX #$C400	* point to data to be fetched
        LDAA $102E	* clear RDRF bit if set
        LDAA 0,X	* get first data byte
START	STAA $102F	* store data in SCI data register
SEND	LDAA $102E	* read SCI status register
        ANDA #$80	* send data byte
        BEQ SEND	* wait for empty trasmit data register
READ	LDAA $102E	* read SCI status register
        ANDA #$20	* extract RDRF bit from status register
        BEQ READ	* branch true: SCI RDR not full; false: SCI RDR full
        LDAA $102F	* read data from SCI RDR 
        STAA 0,Y	* store data byte
        INX		* increment fetch pointer
        INY		* increment storage pointer
        CPX #$C41F	* done sending data?
        BEQ DONE	* branch if done
        JMP START	* if not, get next data byte
DONE	BRA DONE	* yes, stop here