AB SLC505 Remote I/O

Have 1746-NT4 Thermocouple card installed on remote I/O rack working thru channel 0. I need to program another channel and need help. This is the Block Transfer read and write. Thanks

SOR XIO N30:0/12 XIO N30:0/13 BTW 2 2 0 N30:0 N40:0 M0:1.100 4 EOR
SOR XIO N34:0/12 XIO N34:0/13 BTR 2 2 0 N34:0 N50:0 M1:1.200 8 EOR

We have to know exactly what king of help you need.

Are you having problems communicating with the module or do you need to know how to configure a channel or channels?

If you need to know how to configure the channels you can check out chapter 5 of the manual. You can find the manual at A-B's web site:

http://www.ab.com/manuals/io/1746/1746-um007a-en-p.pdf

Good Luck,

(8{)} ( .)

(Yosi)

I need help programming block transfers for Remote I/O. To get two channels working on thermocouple card. Chapter 5 does not help me. Thanks

RIO is the problem you have!

As you have stated, your problem is not knowing how to do BT programming. That is not covered in the manual for the 1746-NT4 Thermocouple card so it really does you no good in that respect. So, look in your SLC500 manual for BT programming. It is in chapter 8 in the version I have which is dated Sept. 2001. Now, once you have worked though that problem, you have to accomplish all that the TC card manual tells you but you must use the RIO/BT features to do it. It is really not all that complicated. Follow these steps:
1. Set up all the data files in your processor if you have not already.
2. Instead of using copy and move files to write to the TC module, you have to do the same thing by sending the data via a BTW.
3. To get status/data back from the TC module, you will have to use a BTR instruction to get that.

In any event, you have to plan where the data will come from that you will write to the TC module and where you will place the data that you will BTR from the TC module. It takes careful planning to accomplish all of this but it can be done. The reason you were not able to find any help in chapter 5 of the TC manual is that it assumes the module is in a local rack.

Hope this helps some!

maybe this is simper than it seems ...

Greetings 1stwave,

maybe I'm missing something here so feel free to ignore all of this if I’ve misunderstood your problem ...

are you SURE that you “... need help programming block transfers”? ... I’ve got a hunch that the block transfers you already have are fine just like they are ... I’ll bet my pocket change that all you really need to do is make sure that the second configuration word in your BTW Data File is properly set up for the second channel (this is where the Chapter 5 reference that Yosi mentioned comes in) ... and then all you should have to do after that is look for the incoming data from the second channel in the second word of the BTR Data File ...

first basic idea: the Block Transfer Write transfers a BLOCK of data to your input module in order to configure the channels for the module ... and since the BTW that you presently have programmed is already set up to transfer a four-word BLOCK of data, then I don’t think that you need another BTW ... note that in Chapter 5 the maximum length of the block of configuration data would be 4 words ... you’ve already got four words specified in your BTW instruction ... so that piece of the puzzle should be good to go ...

another basic idea: the Block Transfer Read transfers a BLOCK of data from your input module in order to bring in the information from the module’s channels ... and since the BTR that you presently have programmed is already set up to transfer an eight-word BLOCK of data, then I don’t think that you need another BTR ... note that in Chapter 5 the maximum length of the block of input data would be 8 words ... you’ve already got eight words specified in your BTR instruction ... so that piece of the puzzle should be ok too ...

in other words, if I understand your problem correctly, then I think that the guy who originally programmed your SLC has already set up the block transfers to take care of all four available channels on your input module ...

suggested plan of attack: let’s just assume (gosh, I hate that word) for a moment that the configuration that you require for your second channel is exactly the same as the configuration that you presently have set up for your existing channel ... if that is truly the case, then just go to N40:0 and find out what value is currently stored there ... then manually type that same value over into N40:1 ...

next run the system and take a look at the value which is showing up at N50:1 ... I’ve got a hunch that you should be very happy with the results ... if I’m right about what you’re trying to do, then N50:1 should contain the input data from your second channel ...

if none of this works, don’t get discouraged ... just post again and give us some more details to work with ... the more details, the better ... I’m sure that we can come up with an answer to help you out ...

finally ... all of this is based on the assumption (and I still hate that word) that your first channel is already working correctly ... if it is, then the block transfers that you already have are ok ... so if all that you want to do is to configure and enable an additional channel on the same module, then you really don’t need any more block transfers ... you just need to plug the proper configuration into the proper word of the Block Transfer Write’s Data File ... and then look for the incoming data in the proper word of the Block Transfer Read’s Data File ...

let us know how this works out for you ... and welcome to the forum ...