VERNIER SOFTWARE
CHEMISTRY AND BIOLOGY PROBES
WITH THE TI CBL AND
TI-73, TI-82, TI-83, TI-83 Plus, TI-85, TI-86, TI-89, TI92, AND TI-92 Plus
I. OVERVIEW
II. MEMORY REQUIREMENTS AND MAXIMUM
DATA
III. GROUP FILES
IV. SENDING GROUP
FILES
V. UNGROUPING FILES
VI. PROTECTED PROGRAM
FILES
VII. PERFORMING EXPERIMENTS WITH CHEMBIO
VIII. USING THE
HEART RATE MONITOR
IX. USING THE VERNIER EKG
SENSOR
X. OVERVIEW OF EACH PROGRAM
XI. PROGRAM
DESIGN NOTES
I. OVERVIEW
This document describes the use of a group of programs that support
Vernier Software chemistry and biology probes for use with a TI calculator
and the TI Calculator-Based Laboratory (CBL) System. The following Vernier
probes are directly supported: Vernier Direct-Connect Temperature Probe, pH,
Pressure Sensor, Colorimeter, Voltage Measurement Leads, Conductivity Probe,
Dissolved Oxygen Probe, Barometer, Relative Humidity Sensor, Biology Gas
Pressure Sensor, Respiration Monitor Belt, EKG Sensor, CO2 Gas Sensor, Heart
Rate Monitor, Exercise Heart Rate Monitor, Standard Temperature Probe, Quick
Response Temperature Probe, Ion Selective Electrodes, Thermocouple, Flow
Rate Sensor and Turbidity Meter. The Texas Instruments Temperature Probe,
Voltage Probe, and Light Probe are also supported.
II. MEMORY
REQUIREMENTS
This entire set of programs may require more than half the available
memory on the calculator. If you run into memory errors, it may be necessary
to delete one or more programs from the calculator. If there are certain
data collection modes you are not using, e.g. Trigger, you can delete the
CMBTRIGG program associated with this mode. (You will find a description of
each program later in this document.) You may also want to consider deleting
the CMBHEART and CMBEKG programs if you are not using the Heart Rate Monitor
or EKG sensor.
If you reset your calculator, then load the CHEM-BIO group file, the
maximum number of point you can collect with all three probes on the TI-73
200, TI-82 is 99, the TI-83 300, TI-83 Plus 512, the TI-85 100, the TI-86
512, the TI-89 512, and the TI-92 350.
III. GROUP FILES
The CHEM-BIO group file is fourteen programs that have been grouped
together. Groups of files for the TI calculator always have a
"??g" suffix where "??" represents the various
calculators: 73, 82, 83, 85, 86, 89, or 92. Individual program files have
the extensions "??p". The extensions on the filenames appear only
on the computer and do not appear when you see the program names on the
calculator. The easiest method of loading all fourteen programs on to your
calculator is to transfer the CHEM-BIO.??g group file. (Note: the TI-83 Plus
calculator is handled differently. See the Readme file in the TI-83 Plus
folder of the Vernier Data Collection disk.)
IV. SENDING GROUP FILES
You will need to use TI-Graph Link to send the CHEM-BIO.??g group file to
your calculator. The actual steps will depend upon the calculator and
computer you are using. If you are unsure of this process, refer to the
Graph Link manual for the calculator and computer you will be using. Not all
calculators are handled the same.
V. UNGROUPING FILES
You may prefer to "ungroup"
the CHEM-BIO.??g file for archiving on a hard drive. Before you do that, it
would be best to create a folder or subdirectory on your hard drive for the
group file. The programs can then be stored in a common area on your hard
drive after being ungrouped. The files can be ungrouped by choosing the
Ungroup Files option in the TI-Graph Link program. Ungrouping the file will
make the following fourteen programs available: CHEMBIO, CMBCALIB, CMBCALS,
CMBDERIV, CMBEKG, CMBGRAPH, CMBHEART, CMBINTGL, CMBMONIT, CMBPOINT,
CMBREGRS, CMBTIMEG, CMBTRIGP, and CMBTRIGG. The TI-Graph Link will also
allow you to download all fourteen programs from the computer to the
calculator.
VI. PROTECTED PROGRAM FILES
The calculator programs described, except for the TI-85, have been
protected so that they cannot be edited on the calculator. This feature
prevents students from accidentally corrupting a program. The easiest way to
edit protected files is with the TI-Graph Link program. The TI-Graph Link
manuals describe the protecting and unprotecting process.
VII. PERFORMING EXPERIMENTS WITH THE CHEMBIO PROGRAM
The
CHEMBIO programs function together to provide a wide range of options as you
create and run experiments. After all fourteen programs have been loaded,
run the CHEMBIO program. (On the TI-83 Plus run the ChemBio application.)
The CHEMBIO program uses a series of menus to set up different types of
experiments with a combination of the probes described in the following
section.
The following general description applies to the use
of these programs on the calculator. For specific help in executing programs
on the calculator, refer to the manual that came with the calculator.
To begin, turn on the CBL and link the Calculator and CBL with
the black cord that came with the calculator. Make sure that the plugs are
firmly pushed into the I/O port on the bottom edge (or the top edge on the
TI-92) of the calculator and CBL. Connect the appropriate probes starting
with Channel 1 (CH1) found on the top edge of the CBL. On the calculator run
the CHEMBIO program. After an introductory screen, the following MAIN MENU
will appear:
***MAIN MENU***
1:SET UP PROBES
2:COLLECT
DATA
3:VIEW GRAPH
4:VIEW DATA
5:FIT CURVE
6:RETRIEVE DATA
7:QUIT
*****************************************************************
TI-85
and TI-86 users will see slightly different menus because the TI-85 and
TI-86 menus are limited to 5 elements in a menu, also the menu items can
only have 5 characters. The MAIN MENU on the TI-85 or TI-86 will be:
***MAIN MENU***
SETUP=SET UP PROBES
COLL =COLLECT DATA
VIEW
=VIEW GRAPH
DATA =VIEW DATA
MORE =MORE
The MORE option will bring up this menu:
FIT C=FIT CURVE
RETRI=RETRIEVE DATA
QUIT =QUIT
RETRN=RETURN
The RETRN option will bring you back to the first part of the MAIN MENU.
When selecting MORE be sure to use the [F5] key, not the [MORE] key on the
calculator. NOTE: the menus in the following description will match the
TI-82, TI-83, and TI-92. The TI-85 and TI-86 menus will differ
slightly.
*****************************************************************
The first option, SET UP PROBES, is used to 1) enter the number of active
probes, 2) choose a probe, 3) enter the CBL channel number for the probe,
and 4) choose the method of calibrating Vernier probes. After you select
this option, the calculator will attempt to communicate with the CBL. If the
CBL is not powered up or the CBL and calculator are not properly linked, an
error message will appear. Check to see that the link cord is firmly
connected to each device and that the CBL is powered up - press the
[ON/HALT] button on the CBL. Correct any problems before continuing. The
calculator will then ask you to enter the number of probes and then the
following menu will appear:
SELECT PROBE
1:TEMPERATURE
2:PH
3:PRESSURE
4:COLORIMETER
5:VOLTAGE
6:CONDUCTIVITY
7:MORE PROBES
These options represent the following
Vernier Software probes:
Vernier Direct-Connect Temperature Probe, pH
System, Pressure Sensor, Colorimeter, Voltage Measurement Leads, and
Conductivity Probe. The option TEMPERATURE and can be used either with a
Direct-Connect temperature probe or with the TI temperature probe that comes
with the CBL. The option VOLTAGE can be used for the Vernier Voltage Probe
and TI Voltage Probe that come with the
CBL. If you select the option
MORE PROBES, you will get another list of probes:
SELECT PROBE
1:D.OXYGEN
2:BAROMETER
3:LIGHT
4:REL HUMID
5:BIO
PRESSURE
6:HEART RATE
7:MORE PROBES
The first six
options represent the following Vernier probes: Dissolved Oxygen Sensor,
Barometer, Light Sensor, Relative Humidity, Biology Gas Pressure Sensor, and
Heart Rate Monitor. The option LIGHT can be used for the Vernier Light
Sensor or the TI Light Probe that came with the CBL. If you select the
option MORE PROBES, you will get another list of probes:
SELECT PROBE
1:VERNR STD TEMP
2:VERNR QIK TEMP
3:THERMOCOUPLE
4:RESPIR. BELT
5:EKG
6:C02 SENSOR
7:MORE
PROBES
These options represent the following Vernier probes:
Standard Temperature Probe (can also be used with the Extra Long Temperature
Probe), Quick-Response Temperature Probe, Thermocouple, Respiration Monitor
Belt, EKG Sensor, and the CO2 Sensor. The RETURN option returns you to the
first list of probes.
SELECT PROBE
1:ION SELECTIVE
2:FLOW RATE
3:TURBIDITY
4:RETURN
The above screen(s) will appear up to three times, depending upon the
number of probes you entered, except in the case of the Heart Rate Monitor
and EKG. (These two options run separate programs described later.) After
you select a probe, you will be asked to enter the channel number for that
probe. This program assumes that the probes are connected to the lowest
available channels.
NOTE: It is important to mention another
consideration when setting up an experiment with some probes. Certain
combinations of probes will interact with each other if they are put in the
same solution and connected to the same CBL. Do not use combinations of the
following probes on the same CBL and in the
same solution: Dissolved
Oxygen Probe and Conductivity Probe with each other or in combination with
the pH System or Vernier Direct-Connect Temperature Probe. The calculator
will warn you if a combination will not work together.
After
you enter the channel number for a Vernier probe, you will be presented with
a CALIBRATION menu, except in the case of the Colorimeter. (The Colorimeter
should be calibrated each time it is used. Therefore, when you select that
probe, you will be sent to the PERFORM NEW calibration option described
below.) The following is the CALIBRATION menu for the other Vernier probes:
**CALIBRATION**
1:USE STORED
2:PERFORM NEW
3:MANUAL ENTRY
(when using a Dissolved Oxygen Probe, a fourth option
appears,
4:POLARIZE PROBE)
Option 1, USE STORED, allows
you to load calibration values for the various Vernier probes from a
calculator file. These are "generic" calibrations determined by
Vernier Software. The values will provide reasonably accurate measurements.
However, individual probes differ and you may obtain better results by
performing a new calibration. The CMBCALS program contains these
slope
and intercept values. It is possible to edit this program and enter the
slope and intercept values for your probes.
Option 2, PERFORM NEW, is used to perform a new calibration. To
understand the calibration process, it is helpful to understand the
operation of Vernier probes. During their operation, the probes produce a
voltage that is linearly dependent upon a quantity being measured. For
example, the temperature probe produces a voltage that varies linearly with
the surrounding temperature. During the calibration process, the computer
establishes the linear relationship between voltage and temperature.
Choosing the PERFORM NEW option will allow you to perform a two-point
calibration for the probe that was just set up. The following paragraph
describes the calibration process for a temperature probe. The same general
procedure can apply to most of our probes.
Begin by placing
the temperature probe in an ice bath. As the probe is swirled in the ice
water, monitor the CBL to see the voltage produced by the probe. To monitor
other channels, press the [CH VIEW] button on the CBL. As you repeatedly
press and hold this button, you will be able to cycle through all the
channels. You will be able to see which channel is currently being monitored
by noting the blinking CH 1, CH 2, or CH 3 symbols in the upper left corner
of the CBL display. When the voltage stabilizes, press the [TRIGGER] button
on the CBL. When the voltage stabilizes, press the [TRIGGER] button on the
CBL. You are then prompted to enter the reference value, "0"
(degrees Celsius). Place the temperature probe in a second reference such as
boiling water or room temperature water. The voltage is again monitored and
the [TRIGGER] button is pressed when the voltage stabilizes. Enter the
second reference value measured with a thermometer. A slope and intercept
for the linear calibration curve are then displayed on the calculator and
automatically
loaded into the CBL. You may want to record these values
for future reference (see the section below). This process can be repeated
for other Vernier probes. For help with a particular probe, refer to the
information sheet for that probe.
calibrationsANUAL ENTRY, in
the CALIBRATION menu is an option that may save you time in setting up
future experiments, especially if you have performed alibrations for your
probes. Probes such as
temperature hold their calibration for long time
periods. If you know the slope and intercept values determined in the above
process, you can manually enter these values with this option. Some probes
such as pH and Colorimeter do not hold their calibrations and may need to be
recalibrated prior to their use.
Option 4, POLARIZE PROBE, is
used to polarize the Dissolved Oxygen Probe. When selected, a power-up
command is sent to the CBL. The polarizing process takes thirty minutes and
is necessary for proper operation of the probe.
From the MAIN
MENU you can set up an experiment by choosing the second option, COLLECT
DATA. The following menu provides you with a choice of data-collection
modes.
DATA COLLECTION
1:MONITOR INPUT
2:TIME
GRAPH
3:TRIGGER/PROMPT
4:TRIGGER
5:SINGLE POINT
6:RETURN
The MONITOR INPUT option is used to monitor the active channels with the
calculator and/or CBL. The purpose of this option is to view data at 1.0
second intervals. No data are stored. For most probe combinations, each
active channel will be displayed on the calculator. However, if there is
more than one active probe and the probe combination contains a pH System,
Conductivity Probe, or Dissolved Oxygen Probe, you will only be allowed to
view a single channel at a time and you will be prompted with the following
menu to choose a channel:
SELECT A CHANNEL
1:CH 1
2:CH
2
3:CH 3
4:QUIT
After selecting a channel, the
calculator will display a reading from that channel on the calculator except
in the case of a Dissolved Oxygen Probe or pH system. In the case of these
probes, you will have to monitor their readings on the CBL display. You will
be presented with this message:
MONITOR CBL
DISPLAY. USE
THE
[CH VIEW] BUTTON
TO SELECT
CHANNEL NUMBER X
PRESS
[TRIGGER]
BUTTON TO QUIT.
The CBL will be put in the
"READY" mode and it will display the reading from channel 1. To
monitor other channels, press the [CH VIEW] button on the CBL. As you
repeatedly press and hold this button, you will be able to cycle through all
the channels. You will be able to see which channel is currently being
monitored by noting the blinking CH 1, CH 2, or CH 3 symbols in the upper
left
corner of the CBL display. When you are done monitoring the
channels on the CBL, press the [TRIGGER] button on the CBL and select the
QUIT option on the calculator. If you are monitoring the channels on the
calculator screen, press the [+] key on the calculator to
quit.
The TIME GRAPH option from the DATA COLLECTION menu is
used to graph up to three channels as a function of time. The design of this
option was based on the assumption that most chemistry and biology users
would want a real-time or live display as data are being collected. In most
cases this type of graph is possible but in some experiments a live display
will not be available. A live
display will be produced for either of the
following situations:
1) Only one probe is active and the time between samples is less than 270
s.
2) When more than one probe of the same type is active; the
sample time is greater than 1.00 s for two probes, or greater than 1.25 s
for three probes; and the time between samples is less than 270 s.
Data will not be displayed live in any of the following arrangements:
1) Two or more different probes are being used.
2) The sample time is
less than 1.00 s for two probes or 1.25 s for three probes.
3) The sample
time is greater than 270 s.
After you select the TIME GRAPH option, you will be prompted to enter the
time between samples which is entered in seconds. If you want a live
display, you must take into account the above criteria and enter an
appropriate number.
If you anticipate the data to be collected without a live display, the
time between samples can be in the range of 0.000264 to 0.2 s or 0.25 to
16000 s. (If you have three active probes, the minimum sample time is
0.000364 s.) After the sample time is entered, you will be prompted to enter
the number of data points. The maximum number for the TI-82 is 99, for all
others it is 512, but you may be limited by the available memory. (See
section II for memory requirements.) The CBL will then be set up to collect
data in either live or non-live display as described above. Note: When data
are collected in a live display, you can stop data collection by pressing
the [+] key.
In most experiments involving a time graph, data will be automatically
sent from the CBL to the calculator. However, if the experiment is too long,
the calculator will automatically power down (APD) and data will not be
transferred to the calculator. This will happen in either of the following
situations:
1) The time between samples is greater than 270 seconds.
2) Two or
more different probes are being used and the total experiment is longer than
270 s.
In either case you will be prompted with a message saying that you will
have to choose the RETRIEVE DATA option at the MAIN MENU at the end of the
experiment.
After each experiment is run, the data are stored
in lists on the calculator. The names of the lists are displayed on the
calculator screen after data collection. In general the independent variable
is stored in L1, channel 1 is L2, channel 2 in L3, and channel 3 in
L4.
The TRIGGER/PROMPT option is used to perform experiments in
which the independent variable is entered from the calculator keyboard while
the dependent variable is measured with the CBL probe or probes. For
example, you could use a Pressure Sensor to monitor the pressure of a gas
enclosed in a syringe as the volume changes. When the [TRIGGER] button on
the CBL is pressed, the CBL measures the gas pressure and you will be
prompted to enter the
volume of the gas in the syringe. The independent
variable data, volume in this case, is stored in list L1 and the dependent
variable data is stored in list L2. If more than one probe is active, data
is stored in lists L2 through L4.
Each time you press the [TRIGGER] button, you will get the following
screen:
DATA COLLECTION
1:MORE DATA
2:STOP AND GRAPH
3:PAUSE
If you select option 1:MORE DATA, the CBL will be set up to make another
reading. If you select option 2:STOP AND GRAPH, data collection will stop
and a graph will be displayed. If you select option 3:PAUSE, the calculator
will be put in a pause mode. When you are ready to collect more data, press
[ENTER] on the calculator and follow the on-screen instructions. If the
calculator has powered down due to the APD, turn on the calculator, then
press the [ENTER] key.
The TRIGGER option allows the user to manually collect one sample at a
time when the [TRIGGER] button on the CBL is pressed. Each time you press
the [TRIGGER] button, you will get the following screen:
TRIGGER
1:MORE DATA
2:STOP
3:PAUSE
If you select option 1:MORE DATA, the CBL will be set up to make another
reading. If you select option 2:STOP, data collection will stop and, if you
have two active channels, a graph will be displayed. (The default graph in
this case plots L1 as the independent variable and L2 as the dependent
variable.) If you select option 3:PAUSE, the calculator will be put in a
pause mode. When you are ready to collect more data, press [ENTER] on the
calculator and follow the on-screen instructions. If the calculator has
powered down due to the APD, turn on the calculator, then press the [ENTER]
key.
In either TRIGGER/PROMPT or TRIGGER you can monitor each
active channel during data collection by pressing and holding the [CH VIEW]
button on the CBL. Repeated pressing of this button will cycle you through
the active channels. After you have collected data, you will be returned to
the MAIN MENU.
The SINGLE POINT data-collection mode, Option 5 on the Data Collection
menu, was designed to make measurements easier and more accurate. When
SINGLE POINT mode is used, the CBL waits 15 seconds for the sensor to
equilibrate with the sample being tested, then takes one reading every 0.2
seconds for 10 seconds. These 50 readings are averaged and this average
value is displayed on the calculator screen.
The third option in the Main Menu, VIEW GRAPH, allows you to review
previous graphs. As you view each graph, you will be able to use the left
and right arrow buttons on the calculator to view the coordinates of each
point. These graphs use the "ZoomStat" option to provide automatic
scaling of axes. You may prefer to quit the program to set your own scaling.
The fourth option, VIEW DATA, exits you from the program so
you can view the data.
The fifth option in the MAIN MENU, FIT CURVE, is used to fit data in
selected lists for linear or power regression. Linear and power regression
statistics are calculated, then a regression curve is displayed on a graph.
It is also possible to exit the program, perform a calculation on one of the
original data lists, then return to the program and perform a linear or
power regression using the new calculated list. Here is a list of regression
and list options available in FIT CURVE:
REGRESSION/LIST
1:LINEAR L1,L2
2:LINEAR L1,L3
3:LINEAR
L1,L4
4:LINEAR L3,L2
5:POWER L1,L2
6:POWER L1,L3
7:RETURN
The sixth option on the MAIN MENU, RETRIEVE DATA, is used after long-term
data are collected without a live display. Before you select this option, be
sure the CBL is done collecting data. (The word "DONE" should
appear in the CBL display.)
The seventh option, QUIT, in the MAIN MENU will exit you from the program
and return you to the Home screen.
VIII. USING THE HEART RATE
MONITOR
OVERVIEW
The Vernier Software Heart Rate
Monitor operates by monitoring the light level transmitted through the skin.
A clip is attached to the ear lobe. One half of the clip contains an
incandescent light bulb and the other half measures the amount of
transmitted light. Since the intensity of the light is a function of the
amount of blood in the ear, the output of the Heart Rate Monitor varies
throughout the heart beat. When the light intensity data are collected as a
function of time, a graph of intensity vs. time produces a periodic pattern.
The pattern can be analyzed to determine the heart rate.
The Exercise Heart Rate Monitor consists of a transmitter belt, plug-in
receiver, and a large and small elastic strap. The transmitter belt is worn
just below the chest and held in place by an elastic strap. The transmitter
detects each heart beat through two electrodes with ECG accuracy and
transmits the heart rate information to the plug-in receiver with the help
of a low frequency electromagnetic field. The plug-in receiver wirelessly
receives the transmission, and passes a 3-volt pulse for each heart beat
detected to the CBL. The reception range of the plug-in receiver in 80-100
cm or about 3 feet.
The following material briefly describes the CMBHEART program and its use
with the Heart Rate Monitor, or Exercise Heart Rate Monitor, TI calculator,
and the TI Calculator-Based Laboratory (CBL) System. The primary uses of the
program are 1) to collect and display data produced by the Heart Rate
Monitor 2) to calculate the heart rate in beats/minute and 3) store heart
rate values in a list and graph them vs. time. This program can be run by
itself or it will be run when you choose the Heart Rate Monitor from the SET
UP PROBE option in the MAIN MENU of the CHEMBIO program.
GENERAL DESCRIPTION OF THE PROGRAM
To begin,
connect either heart rate monitor to channel 1 on the CBL. Attach the clip
to the ear lobe, finger tip, or to the web of skin between the index finger
and thumb, or attach the chest belt around your chest. Run the CMBHEART
program or choose HEART RATE from the list of sensors in the SET UP PROBES
option in CHEMBIO. After introductory screens, a menu will ask you whether
you are using an ear clip or chest belt. Then the main menu will appear.
***HEART RATE MENU***
1:COLLECT DATA
2:VIEW LAST GRAPH
3:VIEW BPM GRAPH
4:QUIT
To begin data collection,
select option 1:COLLECT DATA. A graph will be displayed in the screen if you
are using the Heart Rate Monitor. When data are retrieved from the CBL, time
will be stored in list L1 and voltage will be stored in list L2. The data
collected in L1 and L2 is used to draw a waveform which is displayed in the
graph if you are using the Heart Rate Monitor.
The calculated heart rate
is displayed in beats per minute (BPM). The beats per minute for each sample
is stored in L3. If the CBL and either heart rate monitor are unable to
calculate the heart rate, a message saying "COLLECTING DATA PLEASE
REMAIN STILL" will be displayed on the screen. If the calculator
continues to display this message, you may need to move the earclip around,
or
move closer to the receiver until you find a spot that gives you a
better reading. To stop data collection and return to the main menu, press
[ENTER] on the calculator.
The second option in the main menu,
VIEW LAST GRAPH, displays a graph of the last data segment collected along
with the calculated heart rate. This option is helpful when it is necessary
to take a close look at the waveform or just to review what the heart rate
was before data collection was stopped. To quit from this selection and
return to the main menu, press [ENTER] on the calculator.
The
VIEW BPM GRAPH option takes the list of calculated heart rates(in BPM)
stored in L3 and plots them vs. time. The length of time between samples is
estimated to be 10 seconds. To read the points plotted on the graph press
the right arrow direction key located at the top right hand corner of the
calculator. This option is very useful if you are performing an experiment
which involves calculating an individuals recovery time or the effect of
miscellaneous stimuli on heart rate. To quit from this selection and return
to the main menu, press [ENTER] on the calculator.
IX. USING
THE VERNIER EKG SENSOR
OVERVIEW
The following material briefly describes the
CMBEKG program and its use with the EKG Sensor, TI Calculator, and the TI
Calculator-Based Laboratory (CBL) System. The primary uses of the program
are 1) to collect and display data produced by the EKG Sensor 2) graph the
EKG data vs. time and allow the user to trace the data points for analysis
of the EKG waveforms. This program can be run by itself or it will be run
when you choose the EKG Sensor from the SET UP PROBE option in the MAIN MENU
of the CHEMBIO program.
GENERAL DESCRIPTION OF THE
PROGRAM
To begin, connect the EKG Sensor to channel 1 on the
CBL. Place the electrode tabs along the subject's arms or legs as described
in the EKG manual. Connect the three sensor leads to the electrode tabs. Run
the CMBEKG program or choose EKG from the list of probes. The following main
menu will appear.
CHEM-BIO EKG
1:COLLECT DATA
2:VIEW
GRAPH
3:RETURN
To begin data collection, select COLLECT DATA. Once selected the screen
on the calculator will clear. The program will collect two seconds of EKG
data. When data has been collected, a graph will be displayed and time will
be stored in list L1 and voltage stored in list L2. To collect more data,
press ENTER and select YES from the REPEAT menu. To stop data collection and
return to the MAIN MENU, select NO from the REPEAT menu.
The
second option in the MAIN MENU, VIEW GRAPH, displays a graph of the last
data segment collected. This option is helpful when it is necessary to take
a close look at the graph. To quit from this selection and return to the
MAIN MENU, press [ENTER] on the calculator.
The last option
RETURN will exit the program if you are running it by itself, or return you
to the CHEMBIO MAIN MENU.
X. OVERVIEW OF EACH PROGRAM
The CHEMBIO program will
call the other programs depending upon the options you choose. Each program
is briefly described below.
CHEMBIO - This is the main program
that controls the set up of the probes and the experiment. Begin by running
this program.
CMBCALIB - This calibration program provides
three options allowing you to: 1) perform a new calibration, 2) manually
enter the slope and intercept for a known calibration, or 3) to use a
default calibration (see CMBCALS). For specific help in performing a new
calibration, refer to the information sheet that came with each sensor.
CMBCALS - This file contains Vernier Software slope and
intercept calibration values for the various probes. These values will give
you reasonable data but you may prefer to calibrate each sensor
individually. Once you have calibrated a specific probe, you may want to
replace the Vernier calibration values in this file with your new values.
This file can be edited to contain the new values. When you select the USE
STORED calibration option, your values will then be loaded. Text that is
used on the graphs is also contained in this program. Note: CHEMBIO must
ungrouped before you can edit this program with new calibration
values.
CMBDERIV - This program is used to view graphs of the
first and second derivative of pH-volume data collected in acid-base
titration experiments. It assumes that the independent variable, volume, is
in list L1 and the dependent variable, pH, is in L2. When the program is
run, the first derivative (delta pH/delta volume) is stored in L4 with the
corresponding volume in L3. The second derivative (delta^2 pH/delta
volume^2) is stored in L6 with the corresponding volume in L5. To take the
derivatives, exit the CHEMBIO data-collection program and run the CMBDERIV
program. The program will create three graphs; 1) pH vs. volume, 2) the
first derivative vs. volume, and 3) the second derivative vs. volume.
CMBEKG - This program is run when you choose the EKG sensor from the list
of probes presented during the probe set up. A complete description of the
program appears below.
CMBGRAPH - The CMBGRAPH program contains
graphing routines that are used in presenting graphs.
CMBHEART
- This program is run when you choose the Heart Rate from the list of probes
presented during the probe set up. A complete description of the program
appears below.
CMBINTGRL - This program calculates a numeric integral for a graph of L2
vs. L1.
CMBMONIT - This program allows you to monitor any or all of the three
analog channels. Data will be displayed on either the calculator or CBL
depending upon the combination of probes.
CMBREGRS - This
program calculates linear and power regression statistics and selected
lists. It also allows you to plot a linear or power regression curve on a
graph.
CMBPOINT - The SINGLE POINT data-collection mode was designed to make
measurements easier and more accurate. When SINGLE POINT mode is used,
the CBL waits 15 seconds for the sensor to equilibrate with the sample being
tested, then takes one reading every 0.2 seconds for 10 seconds. These 50
readings are averaged and this average value is displayed on the calculator
screen.
CMBTIMEG - This program produces graphs of active channels as a function
of time. Live and non-live displays are produced depending upon the
combination of probes and length of experiment.
CMBTRIGP - This
program will allow you to collect data such as Boyle's law data that may not
be time dependent. The program will prompt you to input an independent
variable such as volume. The CBL will then measure a dependent variable such
as pressure.
CMBTRIGG - This program uses the [TRIGGER] button
on the CBL to collect data from each active channel. Each time you press the
[TRIGGER] button, data are stored in the CBL. At the end of the experiment
the data are retrieved from the CBL and stored in lists on the calculator.
XI. PROGRAM DESIGN NOTES
These programs have been written
to support Texas Instruments and Vernier probes with the CBL. We hope they
help you perform a variety of experiments with this exciting technology.
Please feel free to share these program with other teachers and students.
Hopefully they have been written in such a way that you can modify them for
your particular application.
The CMBHEART and CMBEKG programs
were designed by Scott Holman and written by Matthew Denton. The remainder
of the CHEM-BIO programs were written by Matthew Denton and Rick Sorensen.
The programs were designed by Rick Sorensen, Dan Holmquist, Scott Holman,
and Matthew Denton. Please contact us if you have any
questions
concerning these programs or the use of our probes with the programs.
June 1, 1999
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