[SOLVED] Writing CHARs

Hi!

I'm using S7-400 series PLC with Step 7 and TP1200 panel with TIA Portal V13.

I have trouble finding out, how can I write CHAR coded letters straight to DB? I have a field on screen with tag with datatype of char, but still I can't write characters to the db... I have to choose display format and there's no char type in the selection.

How am I able to solve this problem?

Br,

Matilda

Hi Matilda

first of all do you use WinCC Comfort/Advanced or WinCC Professional Runtime in TIA Portal?

The you have to be careful. When you use a string in the DB then there are the first 2 bytes the maximum length and the actual length of the String. so you cannot use in HMI a Char  or you have to add 2 bytes to the absolute address. When you use a string in PLC and a String datatype in HMI then everything is OK because both know the fiste 2 Bytes Lengh information.

Please post some screenshots where we can see the DB and the HMi Tag, so that we know how you have programmed the tags.

Bye Murof

try with String.

good luck.

Uh... I programmed tags as Char since I used Mitsubishi panels before with this same project, and there it was possible to write straight chars to db, without using strings...

And with string... get's quite difficult... why there isn't a possibility of writing chars from the panel?? I only need one char, and with the string, it takes more memory than with the old project with old panel...

Thanks for the answers though!

Ah, problem solved.

The datatype in my DB is array [0..x] of CHAR, and in HMI tags the same. But in the I/O-field, the format is string. Then I can type straight the CHAR type data to the db.

Hi Matilda,

can you please show your solution, I am strugling with the same issue.

LeftPrefixArray[0] <--- array[0..3] of Char

Best regard

Martin