11
Chapter 3
Functional Details
Analog input modes
The OM-NET-1608 can acquire analog input data in two basic modes – software paced and hardware paced.
Software paced
You can acquire one analog sample at a time in software-paced mode. You initiate the A/D conversion with a
software command. The analog value is converted to digital data and returned to the computer. Repeat this
procedure until you have the total number of samples that you want.
The sample rate in software paced mode is system-dependent and can range from 1000 S/s to 5000 S/s on local
networks (lower over the Internet or wireless networks).
Hardware paced
You can acquire data from up to eight channels in hardware-paced mode. The analog data is continuously
acquired, converted to digital values, and written into the FIFO buffer on the device until you stop the scan. The
FIFO buffer is serviced in blocks as the data is transferred from the FIFO buffer to the computer memory
buffer. You start a continuous scan with either a software command or with an external hardware trigger event.
The maximum sample rate in hardware paced-mode from one to eight channels is 250 kS/s aggregate on local
hardwired networks (may be lower over the Internet or local wireless networks).
External components
The OM-NET-1608 has the following external components:
Screw terminals
LED status indicators
Ethernet connector
External power connector
Factory reset button
Screw terminals
The OM-NET-1608 device screw terminals provide the following connections:
Eight SE or four DIFF (
CH0H/CH0L
to
CH3H/CH3L
) analog input connections
Eight digital I/O connections (
DIO0
to
DIO7
)
Two analog output connections (
AOUT0
,
AOUT1
)
One external clock input (
AICKI
) and one external clock output (
AICKO
) for analog inputs
One digital trigger input (
TRIG
)
One counter input (
CTR
)
One power output (
+VO
)
Six analog ground (
AGND
) and three digital ground (
GND
) connections
The location of each signal is shown in Figure 2.
