Hello.

I try to develop my own FB to work with WP321 in TIA Portal V14.

I have carefully read Manual - Electronic weighing system SIWAREX WP321, but this manual describes more working with WP321 via FB321 (block from application "ready to use" developed by Siemens).

For example, structures for all data records are described in this manual, but how send command ("Service mode On/Off", "Set Calibration Point 0", "Set Calibration Point 1" and etc.) via DR02 isn't described.

I have done some experiments with FB321 and  have seen that DR02 is sent to WP321 via it output interface, for all other data records block uses "WRREC" instruction.

Also Siemens makes that process variable (weight, ADC and etc.) can be directly read from input interface.

For example, with DR14 you can assign process value 1, 2 and after that read them from IDx+8, IDx+12.

Does anybody have description of WP321 I/O interface, and sequence how send commands for calibration, which signals must send back WP321 and so on?

Thank you.

Hello Siwarexi.

Thank you for your reply.

I understand that FB321 is know-how protected by Siemens. And my question was not about publishing code of FB321, but about full description of interface SIWAREX WP321.

The FB321 provides full functionality of SIWAREX WP321 (and requires a lot of space in working and load memory), but in my project I need only calibration from S7-programm, zeroing and weight and ADC value and, of course, error messages handling.

That is why I want develop my own blocks.

Hi Abron,

I have been struggling with the same issue, Siemens support just advices to use the standard block.....small or large.

The delivered blocks are just not usable for everyone..... especially not for integration in a standard.
Way too large.... To make things worse the standard blocks can't be used in PLC SIM because of the know how protection. You simply can't download them in PLCSIM.... 

Why does Siemens not publish how we can can access the registers ourselfs....!?

One way around is to reverse engineer the standard blocks..... (Classic variant) and figure out what is required to read the raw value, but that will take some time, it's so much code....

For now i use the small block (only called once at FirstScan) and after that i just read the raw value from PID +8.

Have you found another way by now ?

best regards,

Remark

Hello,

Is there a simpler sollution made? Or did someone else made a more simplified FB for this?

Hi,

You ask why?

The answer is that FB promoted by Siemens/You is:

1. too large

2. not autonumbered (cannot be used in Software unit)

3. password protected (cannot be migrated into higher TIA version - over the last 4 years I have migrated from 15.1 to 16 to 17 to 18 to 19) - we have no time to search the web for a single block.

The question should be why Siemens does not publish Siwarex module IO description like for AI, DI, FDQ etc... I bought the module, I want the full manual. I can write the function for my own.

Input mapping wp321

0.0 coordinate (byte) 

About coordinate i made some trace and I fond

0.0 life bite

0.1

0.2

0.3 Datarecord sended to module

0.4 service command sendend to module

0.5 ever true (this bit is ever =true)

0.6

0.7

1.0 id_application (byte)

2.0 error code (word)

4.0 status bit (dword) you can fino the status on the siwatool

8.0 process value 1 (real)

12.0 process value 2 (real)

Output mapping

0.0 coordinate (byte)

About coordinate i made some trace and I fond

0.0 

0.1

0.2

0.3 

0.4 data record command

0.5 service command

0.6

0.7

1.0 id_application (byte)

2.0 command code (word)

4.0 external tare value (real)

8.0 to 15.0 reserved byte

Now for create your own fb you have to use RDREC and WRREC and the coordination byte 

For service command

Write the command in command code (output) for example write 1 for service mode on, then set bit 0.5 service command and wait the response i0.4(service command sended) if no error you will see service mode activated in status bit.

For send dataRecord there is handshake to do

Write bit 0.4 data record command =true then wait the response input 0.3 data record sended, now keep out 0.4 data record command = true and use WR_REC to send the data record for example DR3. When wrrec finish you have to change out bit 0.4 to false.

For read data record just use RD_REC without coordination byte.

I hope to help someone to create your own fb with siwarex wp321

The last part that i want to know is the exactly description of the bit present coordination byte input and coordination byte output and how works id_application byte . If someone know the correct description please send to this post.

For undestand these signals i used trace in TIA Portal with the project provided by siemens and I check how the exchangange io are sendend and received.

Best regards