Problem with BTW & BTR in PLC-5

Gsquare

Member
Join Date
Jul 2004
Posts
10
The present system:- Consists of a PLC-5/40 E CPU mounted in a 8-slot chassis. There are several remote I/O panels consisting of five 16 slot chasis (1771-A4B). Each chassis has got a 1771-ASB (remote I/O adapter) daisy chained to each other and connected to the PLC's 1B channel. The various cards already inserted (and working) in these chassis are 1771-IAD, 1771-OAD, 1771-IFE, 1771-OFE and 1771-IR. RSLogix-5 version 3.2.0.0 is used.

What we did to the existing system:- We added two(2) 1771-A3B (12 slot) chassis. Inserted several 1771-IAD and 1771-OAD. Configured them successfully. Tested the discrete I/O and found them to be okay. There were several slots vaccant in both the newly added chassis.

We started facing problems :- When we were asked to insert and configure a 1771-IFE/C module in the new 12 slot chassis. To our great dissapointment we found that although we could insert 1771-IFE/C modlues to these 12 slot chassis,we failed to correctly write the rungs for BTW and BTR. To be more specific the BTW & BTR rungs contain information regarding rack number, group number, slot number, data file etc. . To our utter dismay we found all these fields in the BTW & BTR instruction was becoming ZERO when assembled and tested. That is the rack number, group number, slot number, data file address etc. would become ZERO on being assembled. On a hunch we tried adding ANY analog module (1771-IFE or 1771-OFE or 1771-IR) to the older 16-slot chassis. To our great puzzlement the result was same ( all becomimg BTW & BTR fields becomimg zero). We have got no doubts that the data file word and control word used by us were unique and not used elsewhere.

What could have gone wrong? Any insight by experienced users would be most welcome.

Regards,
Gautam
 
Not having seen the problem I've got two suggestions:

1) Even before entering the rungs try to manipulate the BT file
directly. See if something in the program is clearing this data.

2) Try using another file for the control block. If you don't have another BT file designated use an N file. The BTR and BTW instructions will use 5 integer words as a control block when programmed this way.

Regardless, let us know what the results of the above were.

Good Luck,

(8{)} ( .)

(Yosi)
 
Your Reply to BTR & BTW Problem in PLC-5

Dear Yosi,
No luck so far. Created a brand NEW "BT" and "N" file and used them for BTW & BTR. The results are same. All fields become zero when assembled.

Regards,
Gautam
 
Try making sure your IFE Module is in a group by itself. What adressing are you using in the rack with the IFE module, single slot, 2 slot, or 1/2 slot. In other words, Make sure the module plugged in beside the IFE module is not effecting you.

Bob
 
this is one for the books ...

Gsquare,

I’ve never seen anything like this happen before ...

here’s a basic approach which MIGHT shed some light on your problem ...

start up a new program (offline) for your model and revision number of processor ... then add just ONE rung ... a BTW for one of your IFE modules ... don’t try to download the program ... just see if you can verify it offline ...

here’s one that I just plugged in using RSLogix5 version 6.00.00 ... it worked just fine ...

[attachment]

I’m grasping at straws here but just MAYBE your version 3.2.0.0 software won’t handle the newer 1771-IFE/C modules ... naturally I don't have an older version of the software loaded up or I'd try this out myself ...

if this experiment doesn’t lead to anything useful, is there any chance that you could zip up your .RSP file and post it? ... we’d be glad to take a look at it ...

also ... it would be a good idea to tell us EXACTLY what rack/group/module settings, etc. you are trying to use ... in fact, why not just detail EVERYTHING that you’re trying to set up in the block transfers? ...

and as Yosi suggested:
Have you tried writing directly to the BT file in data view?

and by all means, when you finally DO come up with an answer, PLEASE let us know ... this one is weird ...

cut.jpg
 
Ron said:

I'm grasping at straws here but just MAYBE your version 3.2.0.0 software won't handle the newer 1771-IFE/C modules ... naturally I don't have an older version of the software loaded up or I'd try this out myself

I'd be surprised if this was an issue. The BTR/W configuration just moves words back and forth to the module. The only difference (from a block transfer standpoint) between the series B and C is the size of the communications blocks. The series C has 2 extra words in the read and write blocks.

Regardless, configuring the IFE/C to look like a series B by moving the jumper on the (top of the?) module will circumvent the software issue.

Good luck,

(8{)} ( .)

(Yosi)
 
First, I would double check all of the jumpers.

Make sure everything is set up the way it should be on the IO configuration (each chasis matches what's physically there, single slot addressing, etc.) Then add your cards.

Also, did you enter the block transfer files manually, or did you have Logix generate them?
 
Ron,Yosi,Bob and all the others:

Tried OFFLINE programming. The BTW or BTR ARE getting verified without any error. But when I enter the same rungs in ONLINE mode the rack address, module address, data file address etc. becomes zero. I would soon post the zipped .RSP file as suggested by Ron. By the way my version of RSLogix does support 1771-IFE/C. I tried both manual and auto insertion of rungs- the results are the same.

Regards,
Gsquare
 
Good Morning GSquare,

I'm going to ask you this again. Did you try manually writing into the data table?

Also, try using MOV instructions to write the Rack, Group, Slot, file, and word into the BT structure.

Keep us up-to-date.

(8{)} ( .)

(Yosi)
 
plc problem

I am facing the problem of downloading the plc program to computer, it may be a software or else.

i am having the TOSHIBA PLC T1 MDR 4.40 & MDR 28.
Also having the DOS based TPDS software and having following cable details that i have used for above work

Com 1 port plc

9 pin ----- 8 pin

2 ----- 6
3 ----- 8
5 ----- 5
(7-8) ----- (4-7)
Shorted Shorted


Anil V. Muley.

other E mail is [email protected]
 
still looking forward to that RSP file ...

Gsquare,

first of all ... Yosi has suggested ... and I have seconded his suggestion ... and then Yosi repeated the suggestion ... that you try manually writing into the data tables while online to see if the data values are being changed by something in your program - or possibly by an HMI application ... have you done this? ... how did it turn out? ... this is an IMPORTANT troubleshooting step ... please let us know the results ...

if the values from the above experiment “stick” and if all else fails, then we might need to take a DETAILED look at your hardware configuration ... below is a sample format that I’ve used successfully on several occasions to help customers over the phone ... basically it just provides a systematic approach to show all of the “this-doesn’t-show-up-in-the-RSP-file” hardware settings that can cause annoying configuration problems ...

note: a few “example” entries have been added ... of course, you might have to change these to reflect the actual settings of your system ...

IMPORTANT! ... be sure to “number” ALL (I repeat ALL!) of the slots in the chassis ALPHABETICALLY by starting with the left-most slot as “A” ... using this “letter” approach removes all of the ambiguity which results from “two slot – one slot – half slot” addressing modes, etc. .... then use a separate line to show what type of module you have plugged into each slot ... for modules with “configuration” jumpers or DIP switches, use a separate line to show how each jumper or DIP switch is set ... yes, this “use-a-separate-line-for-everything” approach does use a lot of electronic paper ... but at least it DETAILS everything about the system ...

Chassis A = 1771-A4B
I/O chassis backplane DIP switch 1 = on
I/O chassis backplane DIP switch 2 = off
I/O chassis backplane DIP switch 3 =
I/O chassis backplane DIP switch 4 =
I/O chassis backplane DIP switch 5 =
I/O chassis backplane DIP switch 6 =
I/O chassis backplane DIP switch 7 =
I/O chassis backplane DIP switch 8 =
Jumper for “Using Power Supply Module In The Chassis?” = Y/N

Slot A = 1771-ASB/E Remote I/O Adapter Module
top configuration jumper = left two pins
middle configuration jumper = left two pins
bottom configuration jumper = left two pins
DIP switch S1-1 = on
DIP switch S1-2 = off
DIP switch S1-3 =
DIP switch S1-4 =
DIP switch S1-5 =
DIP switch S1-6 =
DIP switch S1-7 =
DIP switch S1-8 =
DIP switch S2-1 =
DIP switch S2-2 =
DIP switch S2-3 =
DIP switch S2-4 =
DIP switch S2-5 =
DIP switch S2-6 =

Slot B = 1771-IAD
Slot C =
Slot D =
Slot E =
Slot F =
Slot G =
Slot H =
Slot I =
Slot J =
Slot K =
Slot L =
Slot M =
Slot N =
Slot O =
Slot P =
Slot Q =
 
side trip ...

note to muleyanil ... I think that you’ve pressed the “post reply” button at the end of an existing thread and put your post in the wrong place ... try clicking this button from the Q&A board ...

[attachment]

that will give you a fresh new topic all of your own ... welcome aboard ... and don’t forget to register soon ...

cut.jpg
 
Problem with BTR & BTW in PLC-5

Ron, Yosi and all the others who care !,

Here is the zipped file PLC_100.ZIP. Of course I did try to enter the rungs manualy (as opposed to allow RSLogix insert them automatically) but the result remains the same.

Gautam
 

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