Guru
Joined: 05/03/2018
Location: NetherlandsPosts: 5994
| Posted: 09:23am 08 Sep 2023 |
EDIT: ignore the text below, you need a 74LVC123 (retrigerable monostable) to do this, 555 won't work since it cannot re-trigger). But the technique is usable if you choose for a 74xx123 chip.
Set GPIO pin 14 to output, and toggle it every X seconds (X<timeout). something like:
SETPIN GP14,DOUT
PIN(GP14)=1
'MAIN
DO
'whatever needs to be done
PULSE GP14,10 'generate a low 10ms pulse
LOOP
PIN(GP14)=1
'MAIN
DO
'whatever needs to be done
PULSE GP14,10 'generate a low 10ms pulse
LOOP
Pin GP14 connects to ICM7555 pin 2 directly.
The output (ICM7555 pin 3) connects directly to the reset pin (RUN pin). At startup the capacitor is empty, causing the reset pin to be high -> the picomite starts up. It may be desirable to add a diode from the capacitor to 3.3V to make sure the capacitor also discharges fast at a power cycle.
The monostable has a timeout of 1.1 x R x C.
Volhout
Edited 2023-09-08 19:40 by Volhout