Aim AMC429, Справочное руководство

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Software Library Reference Manual for VME 429 93
Section 5 – Transmitter Functions
R R e e p p l l a a y y M M o o d d e e
The replay data block contains the ARINC data words which are organized into
32 minor frames. The minor frame time can be set via the
"Api429CmdTxFrmTimeIni" or "Api429CmdTxFrmTimeIniEx" command. (max.
number of data words depends on the frame time set,
e.g. with frame time 10ms
the max. number in a minor frame is 27 at Hi-Speed operation and 3 at Lo-Speed
operation. The max. size which can be defined is 1023
).
The correct destination half buffer is automatically detected. After a
"Api429CmdTxIni" command the first two calls of this command will setup both
replay half buffers. Then the transmitter can be started.
Subsequent calls of this command should be done after evaluation of the replay
reload flag. After execution of this command the replay reload flag is cleared.
The max. number of data words in a minor frame is calculated as follows:
Definitions:
1 ARINC-Word = 32 Bit + GAP (4 Bit) = 36 Bit
High-Speed = 100 kBits/s
Low-Speed = 12.5 kBits/s
Transfer-Time for one ARINC-Word:
- High-Speed: 360 µs
- Low-Speed: 2.88 ms
Î
Maximum number of data words = Frame-Time / Transfer-Time
See the following page for the layout of the replay data: