Internet PLC Forum

Gary for me the Ladder Logic is easy I have attached a simplified version how I have always done a circuit similar to what I had asked you for. However I totally impressed with your Basic version which works exceptionally well with such a small amount of code however I cannot totally understand exactly how your Basic program does what it does.
L =N -1
IF CALLS & L SETIO CBP ELSE CLRIO CBP ENDIF 
How does it actually turn out to be If Calls Less than be?
My brain keeps seeing if N = 4 then L would be 3 then any Call Value below 3 would be less that 3 but how does that statement IF CALLS & L equal Less Than
Also the same question for the IF CALLS & H SETIO CAP 

I have RELAY[1] that uses the first 8 bits 0 to 7 and only one bit is on at any time

I have another RELAY[2] that can have one or more bits 0 to 7 on
I need to turn on a bit that only turns on if any of the bits in RELAY[2] is greater than the bit in RELAY[1]
Then I also need a different bit to turn on if any bit that is of lower value than the bit in RELAY[1] regardless if any bit that is higher than RELAY[1] is also on.

I am working on a program that is monitoring various inputs and outputs
Inside each of the functions I check to see if there is an error and if so I call a function
that shows the message on the LCD screen which function failed.
What is the best way to prevent the program from exiting that function until the PLC is restarted?
I originally used a long DELAY to hold it but eventually it does exit.

I have attached a simplified version of what you will need to fully test your project
There is no wait statements or interlocking between the open and close as I didn't feel it was necessary at this point in time. However you can add a timer into each direction circuit to insure that the doors cannot be reversed to quickly. After the close cycle is done relay R10 will turn on which can then be used to start a timer used to prevent the Open Signal calling the Open Function and you will see that once the open is completed relay R11 will turn on that can be used to start a timer needed to interlock the close.  
I have allowed for a limit switch at both the Closed position as well as the open position
However you really only require the one for the closed position
You will need to look at the INIT custom function and change the speed in pulses per second as well as the accell rate see notes inside the function
Next you will need to set the required number of step pulses required to go from fully closed to fully open
For testing I set the position to 1,000 1/2 steps for the full open position
You can test this program on the built in simulator and view the results on the build in display
I hope this helps

After reading this post I decide to add my comments as I am very familiar with the type of doors he is talking about.
They are vertical sliding doors that can either be a single door or two doors that meet in the middle and one goes up while the other goes down.
From experience I would not recommend using a stepper motor for that type of door control
Stepper motors by them selves do not have any feed back and therefore the actual position is really never known if the motor fails to step for any reason.
You can however use a lit switch at each end of travel one when the door is fully closed (Home Position) and one when the door is fully open then you can call a stop motor command on the rising edge of each limit.    
If the doors are properly counter weighted then a power failure at any position should not be a problem and yes it is wise to only cause a close or homing command when a button is pressed.
Your only problem is to insure that when you give a close command that the stepper motor will keep stepping in the down direction until it sees the lower limit switch open and when you give an open command the stepper motor will stop at the right count but will also reset if the upper limit is open.

OK I have tested this scenario many times and found the problem is in the Router
I spoke to someone that is well versed in the subject and he stated that it is an issue with the routers and that yes they have been know to issue the same IP to two different devices if they request an IP at the exact same time.
The only solution was to put a delay of 1 1/2 seconds in the startup of one of the PLC's
This now solves the issue as now both PLC's are no longer requesting an IP address at the same time.

I now have a new question
When you monitor a router it will always show the MAC Address, the IP Address as well as a name
However when I connect 1 or more PLC'S the name always shows as (unknown)
I downloaded a node name into each PLC but that did not change anything.
Can anyone tell me if there is a way to show a name of a PLC in the router?

Gary

Your circuit works perfectly however you had a small typo error
TIME[3] = C ' should have been set the seconds

Also I added Date[3] = D 'Set the day of the week
and added SETLCD 2,1 "DAY = " + STR$ (D,2)

Now I was able to test my multiple times and days perfectly

Again thanks for your help

Lorne