**********
* Program BASE_1 (6811)
*
* Toggle switches - hi and low nibbles are X^1 and X^0 where
* X is any base in range 2 - 16.
* For example 44 (base 5) = 24 dec = $18
*
* No error checking.  For example an entry of 50 in base 5 is
* not valid but it will not be caught by this routine.
*
* Switches converted to natural binary and displayed on discrete LEDs
*
* P. H. Anderson, MSU, 26 Sept 91; Jan 14, '93
**********

PSCT	EQU  $C000
DSCT	EQU  $D000
IDSCT	EQU  $D300

STACKTP 	EQU  $0045
REG_BASE	EQU  $1000

PORTB	EQU  $04
PORTC	EQU  $03
DDRC	EQU  $07


	ORG PSCT
	
	LDS #STACKTP
	
	LDY #REG_BASE
	CLR DDRC,Y	* port c configured as 8-bit input
TOP
	LDAA PORTC,Y	* get switches
	STAA TEMP	* retain copy
	ANDA #$0F	* isolate low nibble
	STAA RESULT

	LDAA TEMP	* get the switches again
	LSRA		
	LSRA
	LSRA
	LSRA		* hi nibble to lo nibble
	LDAB BASE	* multiply hi nibble by base
	MUL		
	ADDB RESULT
	STAB RESULT	* hi * base + lo
	STAB PORTB,Y	* output

	BRA TOP		* repeat

	ORG IDSCT

BASE	FCB  10		* this may be 2 thru 16 decimal

	ORG DSCT

TEMP	RMB 1
RESULT	RMB 1