'{$STAMP BS2}
' Flasher2.bs2 - a program to Flash 3 LEDs WITH an FSM
' Each LED can have on times and off times separately programmable in
'   200 ms increments.

LED1	CON	0		' LED 1 is on port 0
LED2	CON	1		' LED 2 is on port 1
LED3	CON	5		' LED 3 is on port 5

Control1	VAR	BIT	' IF set, causes LED 1 to flash
Control2	VAR	BIT	' IF set, causes LED 2 to flash
Control3	VAR	BIT	' IF set, causes LED 3 to flash

State1		VAR	NIB	' Contains the state of the LED1 State machine
State2		VAR	NIB	' Contains the state of the LED2 State machine
State3		VAR	NIB	' Contains the state of the LED3 State machine
				' StateX = 0 means the LEDX is off and not timing.
				' StateX = 1 means the LEDX is on and timing.
				' StateX = 2 means the LEDX is off and timing.


Cntr1		VAR	NIB	' Contains a counter to allow timing between
				'   states for the LED1 State machine
Cntr2		VAR	NIB
Cntr3		VAR	NIB

On_cnt1		CON	1	' the number of 200ms time slices LED1 stays on.
Off_cnt1	CON	4	' the number of 200ms time slices LED1 stays off.

On_cnt2		CON	2
Off_cnt2	CON	1

On_cnt3		CON	2
Off_cnt3	CON	2



' -----------------------------------------------------------

'  Initialization

' -----------------------------------------------------------

	Control1 = 1		' Make it flash
	Control2 = 1		' Make it flash
	Control3 = 1		' Make it flash

	State1 = 0		' start in idle mode
	State2 = 0		' start in idle mode
	State3 = 0		' start in idle mode

	Cntr1 = 0		' start with timer expired
	Cntr2 = 0		' start with timer expired
	Cntr3 = 0		' start with timer expired

' -----------------------------------------------------------

'  Main Program

' -----------------------------------------------------------


main:

	GOSUB	FSM1		' Do FSM for LED1
	GOSUB	FSM2		' Do FSM for LED2
	GOSUB	FSM3		' Do FSM for LED3
	PAUSE 200		' Wait for 1/5 second = time modularity
	GOTO main

' -----------------------------------------------------------

'  State Machine Subroutines

' -----------------------------------------------------------


FSM1:				' Here is the state machine for LED1

	IF (Control1 = 0) THEN LED1_Off	' If not enabled force state 0

	Cntr1 = Cntr1 - 1	' decrement counter - saves code doing it here

	BRANCH State1,[ST1_0,ST1_1,ST1_2]	' Go to behaviors for each state
						' will fall through if invalid index

ST1_0:					' State machine1 state = 0
	IF (Control1 = 1) THEN LED1_On	' See if it should move to state 1
LED1_Off:
	LOW LED1			' Turn off LED
	State1 = 0			' set up next state
	GOTO FSM1_done			' Still to stay off

ST1_1:					' State machine1 state = 1
	IF Cntr1 > 0 THEN FSM1_done	' wait for counter to expire
	LOW LED1			' Need to turn off LED
	State1 = 2			' set up next state
	Cntr1 = Off_cnt1		' set up timer
	GOTO FSM1_done

ST1_2:					' State machine1 state = 2
	IF Cntr1 > 0 THEN FSM1_done	' wait for counter to expire
LED1_On:
	HIGH LED1			' Need to turn on LED
	State1 = 1			' set up next state
	Cntr1 = On_cnt1			' set up timer


FSM1_done:
	RETURN


FSM2:				' Here is the state machine for LED2

	IF (Control2 = 0) THEN LED2_Off	' If not enabled force state 0

	Cntr2 = Cntr2 - 1	' decrement counter - saves code doing it here

	BRANCH State2,[ST2_0,ST2_1,ST2_2]	' Go to behaviors for each state
						' will fall through if invalid index

ST2_0:					' State machine1 state = 0
	IF (Control2 = 1) THEN LED2_On	' See if it should move to state 1
LED2_Off:
	LOW LED2			' Turn off LED
	State2 = 0			' set up next state
	GOTO FSM2_done			' Still to stay off

ST2_1:					' State machine1 state = 1
	IF Cntr2 > 0 THEN FSM2_done	' wait for counter to expire
	LOW LED2			' Need to turn off LED
	State2 = 2			' set up next state
	Cntr2 = Off_cnt2		' set up timer
	GOTO FSM2_done

ST2_2:					' State machine1 state = 2
	IF Cntr2 > 0 THEN FSM2_done	' wait for counter to expire
LED2_On:
	HIGH LED2			' Need to turn on LED
	State2 = 1			' set up next state
	Cntr2 = On_cnt2			' set up timer


FSM2_done:
	RETURN

FSM3:				' Here is the state machine for LED3

	IF (Control3 = 0) THEN LED3_Off	' If not enabled force state 0

	Cntr3 = Cntr3 - 1	' decrement counter - saves code doing it here

	BRANCH State3,[ST3_0,ST3_1,ST3_2]	' Go to behaviors for each state
						' will fall through if invalid index

ST3_0:					' State machine1 state = 0
	IF (Control3 = 1) THEN LED3_On	' See if it should move to state 1
LED3_Off:
	LOW LED3			' Turn off LED
	State3 = 0			' set up next state
	GOTO FSM3_done			' Still to stay off

ST3_1:					' State machine1 state = 1
	IF Cntr3 > 0 THEN FSM3_done	' wait for counter to expire
	LOW LED3			' Need to turn off LED
	State3 = 2			' set up next state
	Cntr3 = Off_cnt3		' set up timer
	GOTO FSM3_done

ST3_2:					' State machine1 state = 2
	IF Cntr3 > 0 THEN FSM3_done	' wait for counter to expire
LED3_On:
	HIGH LED3			' Need to turn on LED
	State3 = 1			' set up next state
	Cntr3 = On_cnt3			' set up timer


FSM3_done:
	RETURN