Depending on the particular application,
software solutions for your organization may already be available
in our software library or alternatively may be custom-developed based on a choice of either
RS-232 or GP-IB interfaces. For software language we currently
recommend either Transera’s HT Basic for Windows or Microsoft’s
Visual Basic. Each of these software languages has distinct
strengths and the ultimate choice will depend on the particular
The full capability of scientific instrumentation may be exploited
by direct computer control. Both Serial (e.g. RS-232) and
Parallel (e.g. GP-IB) interfaces are available to connect and control
programmable devices using a desktop PC.
RS-232: The Serial interface on the PC is normally accessible
through the two rear-connected 9-pin RS-232 ports designated as
COM1 and COM2. Additional RS-232 ports may also be added to
the PC and are typically designated as COM3 and COM4. The
RS232 protocol defines voltage levels and transmission format for
sending data over the serial link. The transmission operation
is characterized by the serial baud rate, word size, start bits,
stop bits and parity. Many PC-compatible devices will set
default conditions of 9600 baud rate, 1 stop bit and no parity.
Some advantages of the RS-232 link include the relative easy
of installation, the low cost and the availability of long connection
lengths (up to 20 meters). Serious disadvantages include the
proliferation of non-standard protocols, and the early versions
of software that often incorporate very poor RS-232 drivers.
GP-IB (IEEE-488): Hewlett Packard originally developed the parallel
IEEE-488 interface bus, and designated it the HP-IB. Due to
its general applicability to instrument control and excellent control
characteristics the bus soon gained widespread industry acceptance
and the IEEE renamed it the GP-IB, for General Purpose Interface
Bus. The original IEEE-488.1 specification defines the bus
protocols as well as the mechanical and electrical characteristics
of the interface. Each device connected to the bus is assigned
a primary address although a secondary address may also be assigned.
In total the IEEE-488 standard allows up to 15 devices to
be connected to a single interface board. Advantages of the
GP-IB include the excellent interface protocol standard and the
multi device capability. Drawbacks include the cost of the
interface board (currently around $300-400) and the incompatibility
between GP-IB boards from different manufacturers. Overall,
however, from an instrument control standpoint the GP-IB clearly
represents the interface of choice.
Jerry Barker Consultants recommend one of two software languages – Transera’s
HT Basic for Windows or Microsoft’s Visual Basic.
HT Basic for Windows. This is Transera’s PC version of
Hewlett Packard’s HP Basic for Workstations (also known as Rocky
Mountain Basic, RMB). HP Basic was originally developed in
the late 1970’S specifically for I/O functionality and as such was
highly recommended for instrument control applications. At
a later date, HP also introduced HP Basic Plus to allow HP Basic
programs to incorporate a Windows-like interface. Following
the introduction of Basic Plus, HP then worked with Transera to
produce a Windows version of HP Basic known (surprisingly) as HP
Basic for Windows. Transera has heavily supported this product
and later versions became known as HT Basic for Windows. The
main advantage of HT Basic over Microsoft Visual Basic is the relative
ease of I/O and the excellent maths capabilities. The downside
is the lack of a compiled version.
See more information on HT Basic for Windows see the Transera
MS Visual Basic. This is Microsoft’s Basic programming language
flagship. It has supreme capability and functionality but
is not always ideally suited to instrument control applications.
Microsoft first introduced Visual Basic following the success
of Windows 3.0. This was their first attempt at a Windows
oriented version of Basic with the language using QuickBasic type
language syntax to build the Windows-based applications. Visual
Basic is now an industry standard programming language with outstanding
versatility and support. An additional advantage for Visual
Basic over software languages such as HT Basic is the ability to
produce a compiled version.
The kinds of software available from Jerry
barker Consultants have been used previously
to produce outstanding, high resolution data in a variety of industries.
Below are a short list of examples:
Electrodeposition Software. Jerry
Barker Consultants have the capability to
develop novel deposition procedures which can be used in conjunction
with our deposition hardware to create advanced electrodeposition
systems. Example systems include those based on: Under Potential
Deposition (UPD); the measurement of the Quasi Rest Potential
(QRP); and Pulsed Plating and Current Reversal regimens. These systems may
be employed for the deposition of complex materials such as compound
and elemental semiconductors, advanced electroactive materails,
conductive polymers, battery materials etc.
In-situ Electrochemistry. Standard electrochemical
methods may be used in conjunction with analytical techniques to
develop in-situ methods. Jerry
Barker Consultants have considerable expertise in
combining electrochemistry with, for example, un-visible spectroscopy,
Raman spectroscopy, x-ray diffraction, as well as thickness and
Electrochemical Voltage Spectroscopy, (EVS). This
method involves a voltage step protocol which provides a high resolution
approximation of the (thermodynamic) open circuit voltage curve
for the electrochemical system under test. Appropriate implemention
of this technique allows direct determination of the differential
capacity data for the system, which have been demonstrated to determine
order-disorder and structural ordering phenomena in alkali insertion
reactions. Kinetic parameters and phase nucleation effects may also
be estimated by careful analysis of the current transient data.
Galvanostatic and Potentiostatic Intermittant Titration Techniques,
(GITT and PITT). These are pulse-transient technques useful
for determining the kinetic parameters in alkali metal insertion
systems. A small constant current (or potential) step in applied
to the system under test, while the transient voltage (or current)
is recorded as a function of time. The change of voltage (or current)
following the pulse determines the dependence of the cell voltage
(or current) on the concentration of the electroactive species.
Electrochemical Impedance Spectroscopy, (EIS). Several
systems are available for these ac impedance measurements.
The careful implementation of this method allows one to reasonablky
de-convolute the indivdual electrode contribution to the overall
cellipedance. Moreover, ohmic, interfacial, kinetic and electrolye
contributions may be determined.
Current Interrupt (CI). These dc impedance measurements
are often carried out on battery and related electrochemiucal systems
and may be considered complementary to the ac (EIS) methods.
The test conditions are carefully controlled to allow an estimation
and de-convolution of the ohmic and non-ohmic (polarization) contributions
to the overall system impedance.
Constant Current Cycling. This is the standard test method
for electrochemical assessment of new battery electrode materials.
The depedence of the electrode voltage versus charge at various
charge/discharge rates may be used to determine material specific
capacity as well as some (limited) kinetic information.