Scanivalve MPS4232 - Setting up an External Frame Trigger; Setting up an External Scan Trigger; Scan-On-Startup Option; Scan Data Output Methods

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MPS4232
Section 3: Operation
The external hardware trigger voltage is input through pins
4 & 5 of the power connector. The MPS accepts a trigger
voltage that is between +5 and +15Vdc at 6.5mA. A wiring
diagram for the power/serial/trigger cable can be found in
Secon 4: Hardware.
MPS4200 has several opons for external triggering which is
controlled by the variable: TRIG. The external trigger can be
used in one of three ways:
1. Hardware Frame Trigger
2. Soware Frame Trigger
3. Hardware Scan Trigger
Opons 1 & 2: the “Frame Trigger” opons allow an external
trigger to release a single frame of data per pulse sensed
by the MPS. This means for each trigger pulse (or soware
command) the MPS will return a single frame of data. The
rate of which the data is output is based on this external
pulse rate.
For opmal external frame triggering, the internal rate of
the MPS should be set ≥25% higher than the external trigger
rate. If a hardware trigger is being used, it must adhere to
the MPS’s trigger voltage requirement. A duty cycle of 50%
is recommended, and the “low” voltage must be as close to
0Vdc as possible.
The soware frame trigger is a command sent to the MPS
that will release a one frame of data per command received.
The trigger can be one of two commands; either a TRIG
command or a <tab> character (9 Hex or Control I). This
works similar to external hardware triggering.
If me stamps are important when external frame triggering,
it is recommended that the MPS’s internal rate be set to at
least 2 mes that of the external rate (or the max scan rate
of the module). This will provide the best resoluon for the
frame me stamps.

To congure the MPS4200 to scan with an external frame
trigger (hardware or soware):
1. Set the variable TRIG to 1
2. Set the RATE variable to a rate at least 25% or faster
than the intended external trigger rate
3. Set the MPS into “scan” mode by sending the
command: SCAN
4. Supply a trigger; either hardware trigger pulse or a
soware trigger. For each trigger pulse, the MPS will
output a single frame of data to the congured des-
naon
Opon 3: the “ Hardware Scan Trigger” opon allows for
a SCAN to be iniated using an external voltage. When
the MPS senses that the trigger input level is “high”
(5Vdc≤voltage≤15Vdc), the MPS will enter scan mode where
it will scan and connuously collect data based on its set
internal rate. The MPS will connue to scan at this rate unl
any of the following condions are met:
• The trigger input level is switched to “low” (<5Vdc)
• The FPS variable is met (frames output = FPS)
• The scan is manually stopped by the user (soware
command or powering o the unit)

To congure the MPS4200 to scan with an external scan
trigger:
1. Set the variable TRIG to 2
2. Set the RATE variable to the desired data collecon
rate
3. Supply a “high” voltage (5Vdc<voltage<15Vdc). The
MPS will collect and output data at the dened rate
unl the trigger input voltage is lowered below the
5Vdc trigger threshold level.

When TRIG is set to 3, the scan-on-startup feature is enabled.
This commands the MPS to start scanning aer the power up
sequence has completed. The data output and desnaon
for this feature must be set as FTP or UDP.
In the event that the FTP server is not ready to handle a
connecon from the MPS4200, the MPS will aempt to
connect unl it succeeds, a STOP command is received
from the serial connecon, or a STOP is received from the
Ethernet connecon. Once scanning is started, data output
connues unl a STOP is received, as described above.
Simply removing power from the MPS will stop the sending
of data. Normally this will cause the FTP server to begin a
me out period waing for data. Aer the me out period,
the FTP server should close the connecon, ush any
unsaved data to disk and close the le. The me out period
of the FTP server is usually congurable. FTP servers may
vary in their operaon so check your FTP server manual for
sengs.
For UDP output, the MPS will output data to the UDP cong-
ured desnaon unl a STOP command is received from the
serial or Ethernet connecon, the FPS variable has been met,
or the MPS is powered down.

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The default method of ASCII data collecon and transfer is
congured using the default Telnet server (port 23) using a