KPCI-3101 — KPCI-3104 Series User’s Manual
External A/D sample clock
The external A/D sample clock is useful when you want to pace acquisitions at rates not avail-
able with the internal A/D sample clock or when you want to pace at uneven intervals.
Connect an external A/D sample clock to screw terminal TB48 on the STA-300 screw terminal
panel (pin 22 on connector J1). Conversions start on the falling edge of the external A/D sample
clock input signal.
Using software, specify the clock source as external. (Refer to the DriverLINX Analog I/O Pro-
gramming Guide provided with DriverLINX.) For the KPCI-3101–4 Series board, the clock fre-
quency is always equal to the frequency of the external A/D sample clock input signal that you
connect to the board through the screw terminal panel.
Analog input conversion modes
KPCI-3101–4 Series boards support the following conversion modes:
•
Single value operations are the simplest to use but offer the least flexibility and efficiency.
Using software, you can specify the range, gain, and analog input channel (among other
parameters); acquire the data from that channel; and convert the result. The data is returned
immediately. For a single value operation, you cannot specify a clock source, trigger source,
trigger acquisition mode, scan mode, or buffer.
Single value operations stop automatically when finished; you cannot stop a single value
operation.
•
Scan mode takes full advantage of the capabilities of the KPCI-3101–4 Series boards. In a
scan, you can specify a channel-gain list, clock source, trigger source, trigger acquisition
mode, scan mode, buffer, and buffer wrap mode using software. Two scan modes are sup-
ported: continuously-paced scan mode and triggered scan mode. These modes are described
in the following subsections.
Using DriverLINX software, you can stop a scan when the hardware fills the host buffer you
specified or when your application issues a stop command.
Continuously-Paced scan mode
Use continuously-paced scan mode if you want to accurately control the period between conver-
sions of individual channels in a scan.
When it detects an initial trigger, the board cycles through the channel-gain list, acquiring and
converting the value for each entry in the channel list (this process is defined as the scan). The
board then wraps to the start of the channel-gain list and repeats the process continuously until
either the allocated buffers are filled or until you stop the operation. Refer to
information on buffers.
The conversion rate is determined by the frequency of the A/D sample clock; refer to
for more information on the A/D sample clock. The sample rate, which is the rate at which a sin-
gle entry in the channel-gain list is sampled, is determined by the frequency of the A/D sample
clock divided by the number of entries in the channel-gain list.
To select continuously-paced scan mode, use software to specify the dataflow as continuous,
continuous pre-trigger, or continuous about-trigger. The initial trigger source depends on the
trigger acquisition mode you use. Refer to
for more information on the supported trig-
ger sources and trigger acquisition modes.
Содержание KPCI-3101 Series
Страница 1: ...User s Manual KPCI 3101 3102 3103 3104 Series PCI Bus Data Acquisition Boards 98150 Rev A 10 99...
Страница 10: ...iv...
Страница 15: ...1 Overview...
Страница 21: ...2 Principles of Operation...
Страница 53: ...3 Installation and Configuration...
Страница 78: ...3 26 Installation and Configuration KPCI 3101 KPCI 3104 Series User s Manual...
Страница 79: ...4 Testing the Board...
Страница 82: ...4 4 Testing the Board KPCI 3101 KPCI 3104 Series User s Manual...
Страница 83: ...5 Calibration...
Страница 86: ...5 4 Calibration KPCI 3101 KPCI 3104 Series User s Manual...
Страница 87: ...6 Troubleshooting...
Страница 94: ...6 8 Troubleshooting KPCI 3101 KPCI 3104 Series User s Manual...
Страница 95: ...A Specifications...
Страница 107: ...B Connector Pin Assignments...
Страница 111: ...C Systematic Problem Isolation...
Страница 145: ...This page intentionally left blank...
Страница 146: ...Keithley Instruments Inc 28775 Aurora Road Cleveland Ohio 44139 Printed in the U S A...