traffic-lights-revisited.txt

\ ******************************************************************************
\ Example of FORTH traffic light management
\
\ Forth version: Flash Forth (http://flashforth.com/) 
\ author: M PETREMANN
\ Creation:     25 mai 2019
\ Modification: 02 nov 2019
\ ******************************************************************************

decimal
-readwrite           \ delete precedents definitions created after -readwrite
marker -readwrite    \ define marker -readwrite
decimal

\ PORTB
37 constant PORTB	\ Port B Data Register
36 constant DDRB	\ Port B Data Direction Register
\ 35 constant PINB	\ Port B Input Pins - unused

: defLED: ( PORTx mask --- <word> | <word> --- mask port)
    create
        , ,             \ compile PORT and min mask
    does>
        dup @           \ push pin mask
        swap 2+ @       \ push PORT
    ;

\ définition LED.xx
eeprom
PORTB $80 defLED: LED.red
PORTB $40 defLED: LED.yellow
PORTB $20 defLED: LED.green

: led.ON ( <pin> ---)
    mset  ;    \ turn pin ON
: led.OFF ( <pin> ---)
    mclr  ;    \ turn pin OFF

: init.LEDs ( ---)
    LED.red     drop
    LED.yellow  drop +
    LED.green   drop +  DDRB mset  ;

: traffic.lights ( ---)
    LED.green   led.ON   3000 ms    LED.green   led.OFF
    LED.yellow  led.ON    800 ms    LED.yellow  led.OFF
    LED.red     led.ON   3000 ms    LED.red     led.OFF  ;
\ trafic.lights execute one light cycle

: lights.loop ( ---)
    init.LEDs
    begin
        traffic.lights
    key? until ;

\ german trafic light style
: D.traffic ( ---)
    LED.green   led.ON   3000 ms    LED.green   led.OFF
    LED.yellow  led.ON    800 ms    LED.yellow  led.OFF
    LED.red     led.ON   3000 ms    
    LED.yellow  led.ON    800 ms 
    \ simultaneous red and yellow ON
    LED.red     led.OFF  \ simultaneous red and yellow OFF
    LED.yellow  led.OFF  ;
\ trafic.lights execute one light cycle

: D.lights.loop ( ---)
    init.LEDs
    begin
        D.traffic
    key? until ;