Astronics OmniBusII - PXIe Trigger Signal Access and Mapping

OMNIBUS II PXIE SPECIFIC FEATURES
5.2 PXIe Trigger Access
The following table shows the PXIe Trigger signals supported by the OmniBus II
PXIe card. All signals are asynchronous to either CLK10 or CLK100. PXIe
Trigger signals can be accessed through the BTICard_ExtDIORd,
BTICard_ExtDIOWr, and BTICard_ExtDIOEnWr functions by passing in the
associated dionum per Table 5.1. These signals can also be monitored using
BTICard_ExtDIOMonConfig with banknum and rise_edge/fall_edge bits per
Table 5.1. For more information on these functions, refer to the API manuals
(e.g., MIL-STD-1553 Programming Manual for BTIDriver-Compliant Devices).
Signal
Direction
API
dionum
API
banknum
API
rise_edge /
fall_edge
PXI_TRIG[0]
I/O
33
2
0x0001
PXI_TRIG[1]
I/O
34
2
0x0002
PXI_TRIG[2]
I/O
35
2
0x0004
PXI_TRIG[3]
I/O
36
2
0x0008
PXI_TRIG[4]
I/O
37
2
0x0010
PXI_TRIG[5]
I/O
38
2
0x0020
PXI_TRIG[6]
I/O
39
2
0x0040
PXI_TRIG[7]
I/O
40
2
0x0080
PXIe_DSTARA
In
41
2
0x0100
PXIe_DSTARB
In
42
2
0x0200
PXI_STAR
I/O
43
2
0x0400
PXIe_DSTARC
Out
44
2
0x0800
Table 5.1—PXIe Trigger Signals
All bi-directional (I/O) signals default to tri-state mode at power-on. They can be
tri-stated, driven high, or driven low with BTICard_ExtDIOEnWr. To drive the
signal, set dioen to TRUE. To tri-state the signal, set dioen to FALSE. Note that
dioval is ignored when tri-stating with this function.
Only one core can drive a particular bi-directional signal at a time. If both cores
are driving the same trigger, the value most-recently written will be driven on the
trigger. For example, if Core A is configured to drive PXI_TRIG[0], then Core B
is configured to drive the same PXI_TRIG[0], the value written to Core B will be
driven on PXI_TRIG[0]. Ensure that other cards in the system do not cause a
conflict by driving a bi-directional signal at the same time as the PXIe card.
PXIe_DSTARC behaves differently than the other PXIe trigger signals. When
PXIe_DSTARC is enabled, the PXIe card drives a continuous 10MHz signal at
50% duty-cycle on this trigger. The PXIe_DSTARC 10MHz output can be
enabled by calling BTICard_ExtDIOEnWr on dionum 44 with dioen set to
TRUE, and disabled by calling BTICard_ExtDIOEnWr on dionum 44 with dioen
set to FALSE. Note that this signal cannot be tri-stated.
5.3 Protocol Sync and Trigger Support
Protocols with Sync and Trigger support (e.g. BTI1553) can interface with the
PXIe Trigger signals by using the SyncDefine or TriggerDefine functions (e.g.
BTI1553_BCSyncDefine, BTI429_ChTriggerDefine, etc). Refer to Table 5.2 for
mappings between protocol triggers (Trigger A-C) and PXIe Triggers (PXI*).
5-2 OmniBus II PCIe/PXIe User’s Manual