R&S RTA4000, Руководство пользователя

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Serial bus analysis
R&S
®
RTA4000
322 User Manual 1335.7898.02 ─ 08
Data Word
Figure 13-42: Structure of a data word
The format of a data word consists of the following parts (see Figure 13-42 ):
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Sync: an invalid Manchester waveform.
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Data: the transferred information (16 bit).
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Parity: checks if there are bit errors during the transmission. The total number of
logic 1 bits for the word (sync bits not included) shall be odd.
Status Word
Figure 13-43: Structure of a status word
The format of a status word consists of the following parts (see Figure 13-43 ):
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Sync: an invalid Manchester waveform.
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Remote Terminal (RT) Address: the unique address of the corresponding RT.
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Message error: indicates an error in the command/data word transmission from the
BC. A logic 1 indicates presence of a message error and a logic 0 indicates its
absence.
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Instrumentation: helps to distinguish between a status word and a command word.
The logic state of this bit shall be 0.
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Service Request: indicates that the RT requires service. A logic 1 indicates a pres-
ence of a service request and logic 0 indicates its absence.
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Reserved: bits reserved for future uses.
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Broadcast Command: a logic 1 indicates that the preceding valid command word
was a broadcast command and a logic 0 that it was not.
MIL-STD-1553 (option R&S RTA-K6)