;;
;; Filename:      led1.sx
;; Reference:     Introduction to Assembly Language Programming
;;                with the Scenix SX Microcontroller, version 1.2
;; Ref Webpage:   http://www.sxtech.com/Downloads/intro_to_sx.pdf
;; Page:          20
;; Webpage:       http://devices.sapp.org/program/scenix/led1/led1.sx
;; Creation Date: 31 May 2000
;; Last Modified: 31 May 2000
;;
;; Description: This program will light up an LED connected to 
;;     any of the 8 Port B (rb) I/O pins.  Put a 470 Ohm or so
;;     resistor between the LED and +5 volts.
;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;


device	pic16c55, oscxt5
device	turbo, stackx_optionx
reset	Start
freq	50_000_000

org	0

Start	MOV	!rb, #0
	MOV	rb, #0
	SLEEP


;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;
; Program notes:
;
; device pic16c55, oscxt5
;	Assembler directive that tells the assembler to have
;	the SX controller to configure itself like a PIC16C55
;	microprocessor and a high-speed oscillator (oscxt5).
;
; device turbo, stackx_optionx
;	turbo = fast execution mode
;	stackx_optionx = ?
;
; reset Start
;	indicates where the program is to start executing.
;	"Start" is a user-defined label.  This label marks
;	where the program will start executing when it is started.
;
; freq 50_000_000
;	Specifies the clock frequency in Hertz.  Not needed by
;	the SX chip, but helps the debugger determine what clock
;	frequency you want to use.  The default value is 50 MHz
;	if none is specified.  The underscore characters are
;	optional and used for readability.
;
; org 0
;	"Origin" -- a directive that instructs the assembler to
;	begin generating code at the specified address
;
; Start
;	A label used to mark a program address.
;
; MOV !rb, #0
;	Write the constant 0 to the port B direction register.
;	0 = output, 1 = input.
;
; MOV rb, #0
;	Writes the data value 0 to the port B register.  Each
; 	pin on port B will then be set to 0 volts.
;
; SLEEP
;	Shuts the processor down in low-power mode.
;