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CHEM-BIO Read Me

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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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