19
Time-to-Digital Converter Octa Channel TDC Manual
The TDC can provide an additional signal which is in correlation to the internal start signal of the TDC. This
signal is not provided with each internal start, but only once at the beginning of each measurement. It is
provided as a low voltage TTL signal to the “GATE OUT” (BNC socket) of the TDC.
The gate out signal can be used e.g. to extend the measurement range of the TDC from the standard
40µs to a virtual unlimited measurement range. For this it is necessary that the TDC triggers the time
resolving application/ source (e.g. laser system) of the customer instead of using a reference signal from
the customer’s application/ source as external start signal for the TDC. This is significantly different to the
normal time resolved operation mode. The length of the extended measurement range is defined one
by one by the acquisition time of the measurement (e.g. an acquisition time of 10ms is used to define a
measurement range of 10ms).
In addition changes in the tdc_gpx3.ini file must be made for the gate out signal to be provided by the
TDC.
The corresponding entry in the tdc_gpx3.ini file is:
Measurement_to_Start_Sync = X
X is either NO or YES.
The default setting is NO
.
“Measruement_to_Start_Sync” = YES must be set for the TDC to provide the gate out signal.
In addition the following entries in the tdc_gpx3.ini must be set as follows:
StartCounter = NO
StartPeriod = 0
4.2.10 Gate Signal Output
The TDC comes with a second Ethernet connector to allow to set the static IP Address of the TDC as well as
to allow a remote hardware reset.
The TDC itself can only handle static IP addresses but no dynamically ones given via DHCP. It comes with
a predefined factory IP address, which can be used to connect the TDC to a PC. In this case the TDC must
be connected directly to a free network connector of the PC (it is recommended to use a PC with a second
network connector available, so that the first one can be used for connecting the PC to a general network).
The network port of the PC must be configured accordingly to the IP address of the TDC which is as follows:
static IPv4 address (predefined factory address): 10.0.0.20
subnet mask: 255.255.255.0
4.2.11 IP Address Setting and Hardware Reset
Time-to-Digital-Converter Octa Channel TDC Manual | Surface Concept GmbH
See also the DLD Device Driver and Software Installation Manual for further details.
Note
