( Traffic Controller on Arduino Uno )
( Chen-Hanson Ting, 5/10/2011       )
( Switches: PC: 0, N; 1, NL; 2, S; 3, SL; 4, W; 5, WL )
(           PB: 2: E; 3, EL )
( LEDs:     PD: 2, nsG; 3, nsY; 4, nsR, 5, nsL; 6, ewG; 7,ewY )
(           PB: 0, ewR; 1,ewL )
 
hex

: init-ports 
	fc 2a c! 3 24 c! 	\ output ports
	3f 28 c! c 25 c! ;	\ input ports, pullup resistors

: seconds for aft 100 for 400 for next next then next ;

: lights ( n -- ) 
	dup 2b c! 		\ PD outputs
	100 / C or 25 c! ;	\ PB outputs, maintain pullups

: switches ( -- n ) 
	23 c@ 100 * 		\ PB inputs
	26 c@ or 		\ PC inputs
	dup cr . ;

: N-S	begin 104 lights 5 seconds
		switches c3a and if 108 lights 2 seconds then
		switches a and if 130 lights 3 seconds then
	switches c30 and until
	;

: E-W	begin 50 lights 5 seconds
		switches 82f and if 90 lights 2 seconds then
		switches 820 and if 310 lights 3 seconds then
	switches f and until
	;

: go 	init-ports 
	begin N-S E-W ?key until drop ;

flush




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\ Above program was written using 328eForth for Arduino Uno Board.
\ 328eForth is available from www.offete.com for $25.
\ You can have a free copy if you send an email to 
\ 	ting@offete.com

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