Timers and delays

A pump should only start once the valves are surely open. A warning lamp should keep shining after the machine has stopped. Both are times, and the chip measures time in ticks.

Ticks and seconds#

One tick lasts 0.5 s, so a second has 2 ticks. If your main loop runs with exactly one yield per pass, every pass is one tick:

sleep waits as well, but during that time the chip does nothing else. For timers that run alongside the rest of the logic you therefore count ticks.

On-delay#

The output only switches on after the input has been on for a while without interruption. The counter runs up while the input is 1 and drops to 0 at once when it becomes 0:

add tOn tOn 1
mul tOn tOn input      # input off: counter to 0
sge out tOn DELAY      # on long enough?

A short tap triggers nothing. That also protects against operating mistakes.

Run-on time#

The other way round, an output stays on for a while after switching off. While the input is on, the counter is charged to full. Afterwards it counts down:

sub tRun tRun 1
select tRun input RUNON tRun     # on: recharge
max tRun tRun 0
sgtz lamp tRun                   # time left?

The template “Lights on presence” in the IC10 coder works the same way.