Spectrum M3i.4830, Руководство по оборудованию

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96 M3i.48xx / M3i.48xx-exp Manual
External (TTL) trigger using multi purpose I/O connectors Trigger modes and appendant registers
External (TTL) trigger using multi purpose I/O connectors
The M3i card series has two additional multi purpose lines that can
be programmed as additional TTL trigger inputs to be combined ei-
ther with the main (analog) external trigger or with some of the chan-
nel trigger modes explained later in this manual.
Please keep in mind that the multi purpose I/O lines need to be
switched to trigger input prior to being operated as trigger input. The
programming of the masks and the multi purpose I/O behaviour is
shown in the chapters before.
TTL Trigger Mode
Please find the multi purpose TTL trigger input modes below. A detailed description of the modes follows in the next chapters..
For all external edge and level trigger modes, the OR mask must contain the corresponding input, as the following table shows:
Edge and level triggers
Rising edge TTL trigger
This mode is for detecting the rising edges of an external TTL sig-
nal. The board will trigger on the first rising edge that is detected
after starting the board. The next triggerevent will then be detect-
ed, if the actual recording/replay has finished and the board is
armed and waiting for a trigger again.
Example on how to set up the board for positive TTL trigger:
Register Value Direction Description
SPC_TRIG_EXT1_AVAILMODES 40501 read Bitmask shwoing all available trigger modes for external 1 (Ext1) = multi purpose X0
SPC_TRIG_EXT2_AVAILMODES 40502 read Bitmask shwoing all available trigger modes for external 2 (Ext2) = multi purpose X1
SPC_TRIG_EXT1_MODE 40511 read/write Defines the external trigger mode for the multi purpose X0 MMCX connector trigger input. The trig-
ger need to be added to either OR or AND mask input to be activated.
SPC_TRIG_EXT2_MODE 40512 read/write Defines the external trigger mode for the multi purpose X1 MMCX connector trigger input. The trig-
ger need to be added to either OR or AND mask input to be activated.
SPC_TM_NONE 00000000h Channel is not used for trigger detection. This is as with the trigger masks another possibility for disabling channels.
SPC_TM_POS 00000001h Trigger detection for positive edges
SPC_TM_NEG 00000002h Trigger detection for negative edges
SPC_TM_BOTH 00000004h Trigger detection for positive and negative edges
SPC_TM_HIGH 00000008h Trigger detection for HIGH levels
SPC_TM_LOW 00000010h Trigger detection for LOW levels
Register Value Direction Description
SPC_TRIG_ORMASK 40410 read/write Defines the OR mask for the different trigger sources.
SPC_TMASK_EXT1 4h Enable multi purpose X0 external trigger input for the OR mask
SPC_TMASK_EXT2 8h Enable multi purpose X1 external trigger input for the OR mask
Register Value Direction Description
SPC_TRIG_EXT1_MODE 40511 read/write Sets the trigger mode for multi purpose X0 trigger input.
SPC_TRIG_EXT2_MODE 40512 read/write Sets the trigger mode for multi purpose X1 trigger input.
SPC_TM_POS 1h Sets the trigger mode for external TTL trigger to detect positive edges.
spcm_dwSetParam_i32 (hDrv, SPC_TRIG_EXT0_MODE, SPC_TM_POS);// Set up ext. TTL trigger to detect positive edges