cf label

[k1w1]

Hi

In one of my programs a  custom function label  is highlighted in green What would I have done to cause this and is it bad.

Is a new version of the T100MD planned , and if so is it likely to be Canbus compatible


Thanks for your time

[support]

Custom function label is highlighted if it is last executed function during online monitoring or simulation. This is to aid debugging you need not be alarmed by it.

What protocol would you need for your CAN bus application?

[k1w1]

1.Thanks for that.  Next problem is with a PWM cust funct ,for some reason the output will not switch off when P=0 if the clock pulse  for the cf ladder line is 0.01 sec but if changed to o.1 sec the function works ok what do ou think could cause this ?   Should I be using a clock pulse with a PWM cf ?


2. Canbus protocol -    probably  J1937

[support]

How is the clock pulse used in this case? Could it be because the scan time of the program is longer than 10ms and the 0.01s clock pulse didn't get to execute because it failed to reach the CF line during the high cycle of the 0.01s clock pulse?

As for CANbus, do you mean J1939? (I am not sure about J1937). J1939 is for in vehicle CAN communication which is much less used in the PLC target applications. I understand that some thought were given to CANopen but not J1939 for the new product under development.

[k1w1]

The program cycle will take approx 30 sec to complete so do you think it is necessary to use a clock pulse in that line  ?


Typo  sorry  J1939 is what we encounter most  it would be nice to use the PLC as a smart IO card to access the truck canbus  for our various special project requirements.

[support]

You use a 0.01s clock pulse if you want that custom function to be executed every 0.01s or to toggle a relay every 0.01s. If the custom function is in a dead loop and take 30 seconds to execute (probably not the best way of programming but it would still work if you REFRESH after every I/O command) then the 0.01s clock pulse is not needed.