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LSD account for digital watch

(As discussed in EM for Concurrency Lecture 6)

agent power() {
derivate
power_s = battery_charge(time) // three-valued 2,1,0
}

agent watch() {
derivate
LIVE = (power_s >= 1)
oracle
power_s
agent
main() { // as specified below
.....
}
agent light() {
}
agent alarm_st() {
derivate
LIVE=LIVEmain
oracle
LIVEmain , displays_s, alarm_s
state
alarm_s = D, set_time = 00.00
handle
alarm_s // 1:Disab, 2:Enab
protocol
displays_s == A & alarm_st == D & !d -> alarm_st = E
displays_s == A & alarm_st == E & !d -> alarm_st = D
} // !d here means that button d has been pressed
agent chime_st() {
}
agent clock() {
}
agent stopwatch() {
}
.......
}

agent main() {
derivate
LIVE=LIVEwatch
oracle
LIVEwatch, main_s, alarm_s
state
main_s = D // an integer 1:Displays, 2:Beep||displays
handle
main_s
protocol
(main_s==D) & (time==set_time) & alarm_s==E -> main_s=B
agent displays() {
derivate
LIVE=LIVEmain
oracle
LIVEmain
state
displays_s = T // 1:Time, 2:Update, 3:Date, etc
handle
displays_s, update_s, upalarm_s
protocol
displays_s==T & !c -> update_s=1,
displays_s==T & !d -> displays_s=D,
displays_s==A & !c -> upalarm_s=1,
.....
displays_s!=S & displays_s!=T &2-min -> displays_s=T
agent disp_date() {
derivate
LIVE = LIVEdisplays & displays_s==D,
"watch_display = date as of clock()"
oracle
LIVEdisplays, displays_s
}
agent disp_time() { ......
}
agent disp_upalarm() {
derivate
LIVE = LIVEdisplays & upalarm_s>0,
displays_s = (upalarm_s==0%4)?A:UA
"watch_display = time as of alarm setting with right digit highlighted"
oracle
LIVEdisplays, upalarm_s
state
upalarm_s = M // 1:Min, 2:TenMin, 3:Hr, 4=0(mod 4): Alarm
handle
upalarm_s, set_time
protocol
!b or 2-min -> upalarm_s=A,
!c -> upalarm++,
"event -> update set_time so as to increment highlighted digit in set_time"
}
..................
}
agent beep() {
derivate
LIVE=LIVEmain & main_s==B
state
main_s
protocol
beep_stop -> main_s
}
} // end main()