Dolphin TCM 515Z, Руководство пользователя

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USER MANUAL
TCM 515Z – 2.4 GHZ IEEE 802.15.4 Transceiver
© 2017 EnOcean | www.enocean.com F-710-017, V1.0 TCM 515Z User Manual | v1.6 | September 2017 | Page 31/46
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MAC Trailer
The MAC Trailer contains the Frame Check Sum (FCS) field used to verify the integ-
rity of the telegram data.
Figure 16 below summarizes the IEEE 802.15.4 frame structure.
Figure 16: IEEE 802.15.4 frame structure
The content of these fields is described in more detail below.
A.2 PHY Header
The IEEE 802.15.4 PHY header consists of the following fields:
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Preamble
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Start of Frame
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Length of Frame fields
The content of the Preamble and Start of Frame fields is fixed for all telegram types sup-
ported by EnOcean devices as follows:
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Preamble = 0x00000000
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Start of Frame = 0xA7
A.2.1 Length of Frame values used by PTM 215ZE and PTM 535Z
Below are reference values for the Length of Frame field for different type of telegrams
used by PTM 215ZE and PTM 535Z:
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Secure commissioning telegram (Default for PTM 215ZE and PTM 535Z)
Length of Frame = 42 bytes (0x2A)
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Secure data telegram (Default for PTM 215ZE and PTM 535Z)
Length of Frame = 24 bytes (0x18)
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Standard commissioning telegram (Optional feature for PTM 535Z only)
Length of Frame = 17 bytes (0x11)
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PTM switch: Standard data telegram (Optional feature for PTM 535Z only)
Length of Frame = 15 bytes (0x0F)