TI505 very basic programming questions

Preface: I'm suddenly charged with maintaining our TI505 after the contractor we've used for 15 years decided we were too far away to continue supporting us. I'm planning to take the next Seimens TI505 Programming/Maintenance class, but that's not scheduled until June, and I need to know at least the basics of this thing now. I've been reading and learning a lot here on this great forum, and it's been a tremendous help. But perhaps people will forgive me if I ask some really basic questions.

Right now I'm just trying to learn to read the program, and it's starting to make sense. But there're some symbols that I don't understand, and don't see a them explained here on PLC.net, so I suppose they may be TI505 specific.

Anyway, can anyone tell me what the :0: symbol represents?

What are MIRW#, MOVW#, and LDC# functions?

Thanks for your help and patience.
Dan

I recommend you down load the Programming Reference Manual:
http://www.sea.siemens.com/autogen/docs/plc/505/manuals/505-8104-5.pdf

It gives detailed explanations of the entire instruction set.

All the instructions you asked about are located in chapter 6, RLL instruction set.


In TiSoft the :0: symbol is a One Shot, and will have an address of OS2, OS3, etc.

The following should get you started, they were cut and pasted from the 505 Workshop software help files:

Move Image Register to Word (MIRW)
The Move Image Register to Word (MIRW) instruction copies a specified number of bits from the discrete image register or the control relay memory locations to a designated word memory location. Up to 16 bits can be copied in a single scan.

When power is passed to the input of a MIRW, the instruction is executed. The operation of the MIRW is defined as follows:

· Up to 16 bits (N) are copied, beginning with the lowers numbered address, which is specified by IR.

· The bits are moved into the work memory location specified by A, beginning with the LSB of the word. If fewer than 16 bits are moved, the remaining bits are set to 0. All bits are copied during a single scan.

· The output is turned on when the instruction is executed.


Move Word (MOVW)
The Move Word (MOVW) instruction copies up to 256 contiguous words from one location to another. The starting address for the words to be moved is specified by A and the starting memory location for their destination is specified by B. All words are copied in a single scan.

When power is passed to the input of the MOVW, the instruction is executed. The operation of the MOVW is described as follows:

· A table of up to 256 (N) words having a starting memory location specified by A are copied.

· If a constant value is specified in A, then the constant is copied to all destination locations.

· The words are copied to a destination beginning at the memory location designated by B.

· The output is turned on when the instruction is executed.


Load Constant (LDC)
The Load Data Constant instruction (LDC) loads a positive integer constant into the designated memory location.

When the input receives power, the LDC instruction is executed. The data constant designated by N is loaded into the memory location specified by A. When the function is executed, the output is turned on.

One more thing

I don't know if you have any experience with any other PLC's, but one thing that can be a gotcha is the bit numbering.
In the 505 series the bits are numbered from 1 to 16. The LSB is bit 16 and the MSB is bit 1.

See Below:

Ken Moore said:

In the 505 series the bits are numbered from 1 to 16. The LSB is bit 16 and the MSB is bit 1.

Click to expand...

That could catch a lot of people out!

Whats the thought behind it ?

Even when i learned PC's and programming at college the LSB was always the lower numbered bit.........

Could it be something as simple and intuitive as... Left-to-Right, starting with "1"? Bit-1 is indeed the MSb.

Of course, that is contrary to the scheme where the the MSb is Bit-15, on the Left, and the LSb is Bit-0, on the Right.

The idea was based on... if you are talking about bit-numbers then you are not talking about a binary-value. Binary values are "weighted" from the Right, starting with "Weight=0". While in normal-think (putting aside the Jewish version, and any similar), reading and counting generally proceeds from Left-to-Right, and usually starts with "1".

TI was trying to be more connected with the Human aspect of the programming relationship.

Consider all of the strange counting relationships we have to deal with in PLCs.

hey dan, congratulations on your new responsiblities!!!!

keep an eye on those wires to the input/output cards, we have had more wires come loose or break on the 505 more than any other plc.

Yeah, watch that bit order.

I just finished re-programming a TI545 for use with a AB Panel View+ (great fun). We use the AB Panel View series here with AB SLC 504's and I already had screens, alarms and messages built, so I modified the TI program to work with my display.

I have most of the messages and alarms assigned to bits of a word (TI allows this ex: V200.1), and when I tested this I found that I had to assign the #1 bit I used in AB to #16 in TI and leave the Panel View alone so it would read correctly.