Flex727

Fieron is referring to the 4 socket limitation. You will need to connect and disconnect to each slave as needed, or on a regular cycle, depending on your application. Just be aware that it will take a large fraction of a second (or two) to perform the disconnect/reconnect process. I have done this successfully, but I sure would like to see an optimized routine for accomplishing this published as a best practice by Unitronics or an experienced programmer.

I looked all through the Help file and never saw that function. Thanks, Joe.

I've got a problem that I need to perform some manipulations with an ASCII string, but it's possible there are NULL characters (0) in the string. The NULL character may only be one of the 2 bytes in one of the MIs that are part of the vector. I need to check the vector for NULL characters and replace them with H-20 (space). Is there a way to do this?

Shouldn't Clark1 first just confirm that SI 9 isn't set to zero? It's quick and easy to check (but you'll need your flashlight): 1) Go into Info Mode by touching an empty spot on the screen for at least 4 sec. 2) Touch the big button "Enter Info Mode". 3) Enter password (the default is 1111), and press the Enter key on the right. 4) Touch the button near the top labeled OPERANDS. 5) Touch the button labeled "Sys int" (2nd row, 3rd column). 6) SI 9 will be in the 3rd row in the middle. The numbers in the 3rd row will likely be "8", "1", SI 9, "0", "0". The 3rd number (SI 9) should be a value between 0 and 100. If it's near zero, touch the value and enter 50 then the Enter key. If the value is already greater than about 10, then you truly have a dead backlight. Alternatively, if you already have Visilogic installed and a programming cable (and a USB-to-serial adapter), you can check it by going online with the PLC and checking the value directly in the Operands window of Visilogic.

Excuse me - I forgot I was viewing the U90 Ladder forum (thought I was in the Vision forum).

SB 172? That can't be right, can it?

I don't see how copying a vector of inputs or outputs to an MI aids in displaying the state of inputs and outputs on the screen. Can you post a screenshot of what you're trying to do, perhaps one for the inputs that you've successfully done?

Just SI 9 for the V1040, right? I don't think SI 7 does anything in the color vision products.

I've found that you can even run two copies of the same version of Visilogic simultaneously and connect to two different PLCs simultaneously (I think at least one has to be through ethernet). This can be useful in a networked environment where two PLCs talk to each other and you want to know what is going on in both places.

My experience is that a coil remains in the state it was last in when the ladder rung stops being executed. This makes sense since the coil had no logic executed to turn it off (if it was last on, for example). This will also crop up when a subroutine is conditionally executed. Any state change, whether bit, integer, or what-have-you, must be actively executed in order to occur - either off or on.

As Joe said, no need to initialize Socket 2 - it's already set to communicate with your PC. Make sure of the following: 1) NAME the PLC with the Set PLC Name function block tied to a Power-Up contact (SB1) Should be SB 2. 2) Address both PLC and PC to the same subnet and make sure there aren't any duplicate addresses. (Looks like you've done that) 3) Use a CROSSOVER cable or an ethernet switch between the PC and PLC. 4) Go to Connection / Communication & OS (or CTRL-F9), - Select Connection Type TCP/IP (Call) - Click on Project Settings and enter the correct IP Address for the PLC, Protocol TCP, Port Number 20256, and the correct PLC Name. Click OK. 5) Confirm settings work by clicking the "Get PLC Information" button.

Good to know! Thanks, Simon. Indeed I was using the newer V570s.

Without a switch it will need to be a crossover cable, won't it?

I accidentally bought a 12v power supply for development work with a v570 and used it for months before I discovered my mistake. I certainly wouldn't want to install a 12v power supply on a project at a customer installation, but I never had a hiccup. Yes, I didn't have any I/O modules attached and that might make a difference, but the Unitronics PLCs are very forgiving when it comes to voltage.

Under the "Store" dropdown, you will find "Load Timer/Counter Current (and Preset)" and "Store Timer/Counter Current (and Preset)". Use those to move the value into an MI or ML, do whatever math you need to and then move back to a timer (same or different one). Bear in mind that the value you receive will be in units of 10ms so anything over a few minutes must go into an ML.

Ah, step 1 will get you every time! I always create a new subroutine for some function and then forget to add it to the Main routine.

No reason the operator has to enter in any numbers - just have a button or spot on the screen for each hole position (use binary text element, with "toggle") and have the operator touch each position that will have a hole. At each position if the bit is on (has been toggled by the operator), then the hole is punched. Reset all the buttons at the end of the metal strip, or as each hole is punched as a visual indicator of progress.

I routinely code for systems with simultaneous multiple masters using MODBUS IP over Ethernet and Vision products. I've never had any issue even when the slaves are also masters to different PLCs. My systems get a bit complex due to the 4 socket limitation and I've created all kinds of crazy situations to shuffle data around to all parts of the system. One difference is that all my PLCs are always on the same subnet - I don't have any experience connecting across different subnets or across the internet.

I've had something similar happen on several occasions. The following procedure has fixed it for me: 1) Download a blank project to the PLC. 2) Initialize and Reset the PLC. 3) Download your project. It seems that somehow the memory space for the images can get corrupted. Downloading a blank project clears that out and then when you download your actual project all will be well.

Rest assured the Timer function works properly in Unitronics PLCs and software, though it's a bit different than other popular PLC programming software. When I'm troubleshooting this type of problem here is what I do: 1) Confirm the subroutine with the Timer Coil is being called by the Main Routine. 2) Confirm the activating contact is actually ON (and stays ON). Go online with the PLC and check that the MB is SET. 3) Confirm that only one instance of the Timer Coil exists. Right click on the description box and select Find. 4) Confirm the Timer value while online with the PLC by clicking on either a Timer contact or coil. If you do all this and the timer is still not working properly, post the code here and someone will look at it.

I find it works better to click and hold for half a sec rather than click multiple times.

Wouldn't it be more straightforward to trigger a 5 sec Extended Pulse Timer (TE) with SB2 and then use that timer's contact to trigger Output 0?

SB2 is the POWER-UP bit - is that not working for you?

Show 300 (minus) "weight from scale"?

Yes, Cara, I know re-engineering VisiLogic is not really feasible. That's why I was a little hopeful that it might be easier to just create a vision compiler for UniLogics. Sure, compilers aren't easy as pie, but people create compilers for multiple platforms all the time. Makes no difference, I said this many times before, Unitronics has the best PLC programming environment in the business - I wish everything in my life worked as well.