3424-XX-UM
ProDAQ 3424 Function Card User Manual
Page 46 of 56
Copyright,
1998-2005 Bustec Production Ltd.
USAGE
This bit can be asserted in the registers assigned to odd channel numbers
and controls the high pass filter of that odd channel and consecutive even
channel
For even channel numbers the write to this bit does not change anything
while readout gives the status of the HPF_EN bit of the previous odd
channel
6
R/W
0
VREFGND_EN
– VREF/GND Input Enable
This bit connects channels to VREF/GND voltage.
0 : channel input switched to front panel
1 : channel input switched to VREF/GND voltage
USAGE
Use only during calibration process
VREF_ON bit selects between VREF and Ground
When calibrating gain (VREF_ON bit switched to VREF voltage) try to
connect only one channel at the time for better accuracy
5
R/W
0
NEG_GND
– Negative Input Grounded
This bit is used to ground the negative input.
0 : Negative input not grounded
1 : Negative input grounded
4
R/W
0
NEG_CPL
– Negative Input Coupling Selection
This bit switches between AC and DC coupling for the negative signal path.
0 : AC coupling selected
1 : DC coupling selected
3
R/W
0
POS_CPL
– Positive Input Coupling Selection
This bit switches between AC and DC coupling for the positive signal path.
0 : AC coupling selected
1 : DC coupling selected
2
R/W
0
TEDS_ON
– TEDS Switched On
This bit is used to connect positive input channel to the TEDS memory reader
circuitry.
0 : positive channel input not connected to TEDS reader (normal operation)
1 : positive channel input connected to TEDS reader
USAGE
The bit from only one channel can be switched on at the time
1
R/W
0
ICP_ON
– ICP Switched On
This bit allows to switch on ICP excitation current.
0 : positive channel input disconnected from ICP current regulator diode
1 : positive channel input connected to ICP current regulator diode
USAGE
The bit NEG_GND has to be set to close the loop of the ICP excitation
0
R/W
0
CHN_EN
– Channel Enable
This bit is used to include the channel in the Data Acquisition process.
0 : channel disabled
1 : channel enabled
5.17. DDS_WX
– DDS Word Register
This is DDS word register. It is used to set up words written to DDS during DDS update phase if
DDS is to be used.
Bit
Access &
Default
Description
15:11
Reserved
10:8
WO
WX_ADDR
– Word X Address
The address of the word. WX_ADDR is in the range from 0 to 4.
7:0
WO
DDS_WX
– DDS Word X