M2p digital input / output card enhancement details


These enhancements are included with each card purchase to increase the versatility of the M2p.75xx-x4 series of digital I/O cards. Please contact DataQuest Solutions should you require any further information.


Multiple Recording

Image showing multiple signal data capture following each rapidly repeating trigger.

Multiple Recording allows the capture of digital signal data (patterns) associated with every one of many trigger events, without having to restart the hardware. The number of pre and post trigger samples can be programmed. This defines the segment (length of signal) that is recorded per trigger. Trigger events which repeat at a very high rate can be recognised with this feature without risk of any being missed. A trigger re-arm period is required immediately after each capture segment, however for the M2p.75xx series of cards this is less than 40 samples (+ any programmed pre-trigger samples that the user has set). Should the user intentionally wish for an extended delay between trigger arrival and each recording this is software programmable too. The memory on the card is divided into several segments of the same size. Each segment will be filled with data when a trigger event occurs.

When using cards of the M2p.75xx series, Multiple Recording may be combined with the Time stamp function to very usefully record the start time of a segment.


Multiple Replay

Image showing multiple digital signal output following each rapidly repeating trigger.

Very similar to Multiple Recording, Multiple Replay allows the replay of digital signal data associated with every one of many trigger events, without having to restart the hardware. Trigger events which repeat at a very high rate will be be recognised with this option, without risk of any being missed. A trigger re-arm period is required immediately after each replay event, as with Multiple Recording this is less than 40 samples. An extended delay between trigger arrival and each replay is software programmable.


Gated Sampling

Gated sampling. Signal data capture period controlled by trigger signals.

Gated Sampling allows recording of a signal controlled by an external gate signal. Data is only recorded if the external gate signal is equal to a programmed level (TTL HIGH or TTL LOW) although it is possible to include some pre & post gate samples too. As with the Multiple-Replay function (above) there is a delay of less than 40 samples between trigger and recording occurs, but easily compensated for by recording some pre-trigger samples too.

The start and end sample of a gate interval may be marked in memory by combining with the Time Stamp feature to record start and end of a gate interval.


Gated Replay

Gated replay. Signal generation period controlled trigger signals.

Gated Repay allows the generation of a signal controlled by an external gate signal. Like Gated Sampling described above, signal data is only replayed if the external gate signal is equal to a programmed level (TTL HIGH or TTL LOW). The delay between trigger arrival and each replay is software programmable.

The start and end sample of a gate interval may be marked in memory by combining with the Time Stamp feature to record start and end of a gate interval.


Time Stamp

Image showing each successive time stamp relative to triggers. The time stamp function allows recording of trigger moments relative to the start of recording or a synchronised external radio clock or GPS card signal. The time stamp function is designed as an enhancement to the Multiple Recording and the Gated Sampling mode, but can also be used without any of these enhancements. The memory of the function is a FIFO buffer and this allows continuous digital signal recording with time stamps. Each time stamp is defined by samples and therefore at the rate of the sampling clock. The relationshipbetween trigger events and the count are set by the modes as described below.

Standard Mode

In standard mode the time stamp counter is set to zero once, with a call to TS_RESET. After this call the counter counts continuously. The time stamp of all recorded trigger events are referenced on this common zero time. With this mode the exact time difference between different recordings may be calculated.

StartReset Mode

In the StartReset mode a time stamp value calculated from a counter value which increments automatically from zero after the initial start of the card, each trigger that comes along is then time stamped. In Multiple Recording mode many such trigger events can be very close together to capture many individual segments of data in a recording. StartRest mode is very useful here as each segment is individually time stamped. The counter only zeros after the end of the complete recording and the restart of the card.

In addition, if this time stamping is used with Gated Sampling instead, a time stamp will show the start and also the end of the gate.

RefClock Mode

The counter is divided in a HIGH and a LOW part. The HIGH part counts the seconds that have elapse since reset of the whole counter and references the seconds signal of an external radio or GPS clock, or any user precise 1Hz signal which is fed into the multi-purpose digital inputs easily accessible on the end plate of the card. The LOW part is reset every second, and defines the position of the trigger event within the current second. This mode allows the absolute time of a trigger event to be recorded.

Note: The HIGH counter part need not be used for counting seconds, it could be used to simply extend the count range for recording the external triggers, this is what happens in Standard and RefClock modes.


Sequence Replay

Sequence Replay example sequence

The Sequence Replay Mode allows greater control over pattern generation with replayed sequences able to switch over from one to another by software command, or a predefined trigger internal or external (LVTTL or TTL). This mode works by splitting the card memory into segments to hold the signal data, each segment allowing a completely different signal pattern to be held (if so desired), it is even possible to simultaneously redefine pattern data for segments whilst other segments are being replayed. This enhanced flexibility is particularly useful for stimulus-response systems where the signal pattern produced must react to a detected signal, or in multi-function test scenarios. For ease of control programming is done via straightforward text and number commands to chose replay segments and loop.



DataQuest Solutions Ltd. | Phone: 01526 557171 | Email: info@dqsolutions.co.uk