Aim MIL-STD-1553 - Page 214

MIL-STD-1553 Reference Manual
200
Chapter 7 – Bus Controller Functions
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Buffer Queue Mode
Value
Constant
Description
0
API_BQM_CYCLIC
Cyclic data storage
1
API_BQM_STAY_LAST
Store once and stop at end of
queue (last index) and reuse
last buffer
2
API_BQM_HOST_CONTROLLED
Do not advance automatically
to next buffer (host controlled)
3
Reserved until status queue is
supported
Note: The Buffer Queue Mode is only processed, if the “Buffer is valid”.
The Buffer Queue Modes affect the Current Buffer Index and thus (in
the future) the Status- and Event Queue Operation of the BC!
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Data Buffer Store Mode
For Receive Operation the following options are valid:
Value
Constant
Description
0
API_BSM_RX_DISCARD
Discard error messages from
the current Data Buffer
1
API_BSM_RX_KEEP_CURRENT
Keep error messages at the
current Data Buffer
For Transmit Operation the following options are valid:
Value
Constant
Description
0
API_BSM_TX_KEEP_SAME
Keep the same Data Buffer at
transfer error
1
API_BSM_TX_GO_ON_NEXT
Go on with the next Data Buffer
in the Buffer Queue
Note: The data buffer store mode is always evaluated at the ‘Transfer-End’:
‘bsm’ = 0:
If a transfer error is detected at the ‘Transfer-End’, the Buffer is not
valid! ‘bsm’ = 1: At ‘Transfer-End’ the Buffer is always valid and it
does not matter, if a transfer error is detected or not. If an error
occurred during a RT-BC or RT-RT transfer, the BC terminates the
transfer with the error detection. Thus, the possible remainder of the
transfer after the error will not be stored in the buffer.