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Write a reusable PLC logic to control a system status light with adjustable On and Off time durations using any language.
Sample:
@twincontrols Here is my finished, corrected version recorded on a .webm file and some screenshots. Thank you for your help.
I have this solution
@twincontrols What are you thinking about? xIsOn, xIsEndOff? It's to have a clean code, to be readable for all.
@joris Yes, I totally understand. You can also use one of the timers output as the input of the other timer and can solve this using 2 rungs. Your solution is great though! Thanks for sharing!
I am new to TwinCAT and am having trouble understanding how to use a TON/TOF inside of a function block.
When I try to make a Function Block called StatusLight, I have the following variables:
//Public Variable with Only Read Access
b_OutputLED : BOOL;
//Public Variables with Read+Write Access
b_InputSignal : BOOL;
t_onTime : TIME;
t_offTime : TIME;
//Private Variables Hidden to the User
fb_timerTON : TON;
fb_timerTOF : TOF;
I want to put the logic for the timers inside the StatusLight function block, but anytime I do that and create an object in the MAIN program, the timers themselves do not operate. I have read on other forums on the internet that you can't do this. Can someone explain why this is to me.
(NOTE: Inside the FB for Status Light, the code for creating the on/off timing sequence is not complete. I wanted the focus of my question to be about why the TON/TOF function blocks can't work inside a new function block)
-Evan H.
@ehixenbaugh You can use function blocks inside a function block without any problem. Your first timer input is expecting b_InputSignal to be HIGH, but in the MAIN program, you haven't set that property yet. And instantiate your function block in MAIN.
FB_MyStatusLight();
@twincontrols Ok I did that and it worked like a charm. Sorry I had some replies that I deleted.