Guru
Joined: 07/08/2011
Location: AustraliaPosts: 6546
| Posted: 08:01pm 30 Nov 2020 |
Does not qualify for "sleakest way" but it might be a start for you
Use any digital pin and switch pulls input to ground. Internal pullup should be adequate but you could use external resistor to 3.3V instead.
A capacitor is always advisable although the debounce timer should stop bounce triggers. The capacitor will reduce the number of calls to the sub.
It assumes that you don't reset the timer anywhere in your program.
OPTION EXPLICIT
OPTION DEFAULT NONE
CONST sw_pin = 10
const debounce = 200
DIM INTEGER sw_action
SETPIN sw_pin, INTB, clicked, PULLUP
DO
IF sw_action = 1 THEN
PRINT "clicked"
sw_action = 0 ' reset the flag
ENDIF
LOOP
SUB clicked
STATIC INTEGER old_sw_state, old_time
LOCAL INTEGER sw_state, new_time, interval
sw_state = PIN(sw_pin)
new_time = TIMER
interval = new_time - old_time
print "*" ' debug info to show contact bounces
IF sw_state <> old_sw_state AND interval > debounce THEN
old_sw_state = sw_state
old_time = new_time
IF sw_state = 0 THEN sw_action = 1 ' only set the flag with switch low
ENDIF
END SUB
OPTION DEFAULT NONE
CONST sw_pin = 10
const debounce = 200
DIM INTEGER sw_action
SETPIN sw_pin, INTB, clicked, PULLUP
DO
IF sw_action = 1 THEN
PRINT "clicked"
sw_action = 0 ' reset the flag
ENDIF
LOOP
SUB clicked
STATIC INTEGER old_sw_state, old_time
LOCAL INTEGER sw_state, new_time, interval
sw_state = PIN(sw_pin)
new_time = TIMER
interval = new_time - old_time
print "*" ' debug info to show contact bounces
IF sw_state <> old_sw_state AND interval > debounce THEN
old_sw_state = sw_state
old_time = new_time
IF sw_state = 0 THEN sw_action = 1 ' only set the flag with switch low
ENDIF
END SUB
(I am one of the lucky ones, it's my left hand that's no use)
Jim