* Popular equates

EXT_RAM_START	  EQU	$0200	* Start of external RAM in U5
BUF_UTLJMP_START  EQU	$ffa0	* Start of Buffalo utility subroutine jump table in ROM
JUMPINST_SIZE	  EQU	3	* Length of jump opcode + 2 byte addr
EOT		  EQU	$04	* ASCII code for "end of transmission"

* Define the entries in the Buffalo utility jump table

	 ORG	BUF_UTLJMP_START
UPCASE	 RMB	JUMPINST_SIZE	* Convert character to uppercase
WCHEK	 RMB	JUMPINST_SIZE	* Test character for whitespace
DCHEK	 RMB	JUMPINST_SIZE	* Check character for delimiter
INIT	 RMB	JUMPINST_SIZE	* Initialize I/O device
INPUT	 RMB	JUMPINST_SIZE	* Read I/O device
OUTPUT	 RMB	JUMPINST_SIZE	* Write I/O device
OUTLHLF	 RMB	JUMPINST_SIZE	* Convert left nibble to ASCII and output
OUTRHLF	 RMB	JUMPINST_SIZE	* Convert right nibble to ASCII and output
OUTA	 RMB	JUMPINST_SIZE	* Output ASCII character
OUT1BYT	 RMB	JUMPINST_SIZE	* Convert binary byte to 2 ASCII characters and output
OUT1BSP	 RMB	JUMPINST_SIZE	* Convert binary byte to 2 ASCII characters and output followed by space
OUT2BSP	 RMB	JUMPINST_SIZE	* Convert 2 consecutive binary bytes to 4 ASCII characters and output followed by space
OUTCRLF	 RMB	JUMPINST_SIZE	* Output ASCII carriage return followed by line feed
OUTSTRG	 RMB	JUMPINST_SIZE	* Output ASCII string until end of transmission (004)
OUTSTRG0 RMB	JUMPINST_SIZE	* Same as OUTSTRG except leading carriage return and line feed is skipped
INCHAR	 RMB	JUMPINST_SIZE	* Input ASCII character and echo back

* Here's our actual program.

	ORG	EXT_RAM_START	* Start code at beginning of external RAM

* "Hello" subroutine, prints "Hello World!" on Serial Comm. Interface.

HELLO:	LDX	#MSG		* Point X at "Hello World!" string
	JSR	OUTSTRG0	* Call appropriate "Out String" subroutine to print
	RTS			* Return from subroutine	

MSG:	FCC	'Hello World!'
	FCB	EOT