I can't seem to get how the API lengh is calculated

XBee & XBee Gateway XBee - 802.15.4
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1

Hi,

Could somebody explain how I get the API lengh because whenever I count it , it is a different number between 7e and checksum.

Thanks in advance
Stuart

2

Have you tried looking at:

http://knowledge.digi.com/articles/Knowledge_Base_Article/What-is-API-Application-Programming-Interface-Mode-and-how-does-it-work/?q=API&l=en_US&fs=Search&pn=1

and

http://knowledge.digi.com/articles/Knowledge_Base_Article/Calculating-the-Checksum-of-an-API-Packet/?q=API&l=en_US&fs=Search&pn=1

3

Yes I have tried looking at several explanations but whenever i count the bits in between 7e and he checksum I get a different number.

4

You need to be counting Bytes not bits.