Interpretation of Bit-String Values i.e from where Bit 0 Shall Start

Forum Rules

Before commenting read Forum rules

Don't comment the topic if you have a new question.

You can create a new topic selecting correct category from Gurux Forum and then create a new topic selecting "New Topic" from the top left.

By deepaks , 22 May, 2020
Forums
General discussion

Hi,

Please tell me Is it the correct interpretation of Value field(for Bit-String Data Type) in following example:

04 10 26 4A

Bit 0 - 0
Bit 1 - 1
Bit 2 - 0
Bit 3 - 1
Bit 4 - 0
Bit 5 - 0
Bit 6 - 1
Bit 7 - 0
Bit 8 - 0
Bit 9 - 1
Bit 10 - 1
Bit 11 - 0
Bit 12 - 0
Bit 13 - 1
Bit 14 - 0
Bit 15 - 0

Thanks in Advance

Kurumi

6 years ago

Hi,

04 10 26 4A = 0010011001001010

In bit-string first bit is on the left side, not at the end. In this way new bits are happened to the end of bit string.

If you download GXDLMSDirector and select "Tools", and "DLMS Translator" and then select "Data to XML tab" you can validate bit string by your self adding your bytes and pressing "PDU To XML" button.

BR,
Mikko

deepaks

6 years ago

Hi Mikko,

Thanks for your Prompt Reply !!!
where is the Bit 0 located extreme left or extreme right

<BitString Value="00000000000000000000000000000000000000001001000000000000000000000000000000000000000000000000000000000000000000000000000000010000" />

Thanks in Advance

Kurumi

6 years ago

Hi Deepak ,

The first bit is located on the left. This is because there might be new bits in the future and if they are added to the left, it will break backward compatibility. This is common example in Image Transfer. Image size might grow and new blocks are needed to send the image.

BR,

Mikko

deepaks

6 years ago

Hi Mikko,

Thanks a lot, now i got the concept behind the Bit-Strings.