VERNIER SOFTWARE 
PHYSICS WITH 
THE TI CBL AND TI-82, TI-83, TI-85, TI-86, and TI-92

   I. OVERVIEW
  II. MEMORY REQUIREMENTS AND MAXIMUM DATA
 III. GROUP FILES
  IV. SENDING GROUP FILES 
   V. UNGROUPING FILES
  VI. PROTECTED PROGRAM FILES
 VII. GENERAL DESCRIPTION OF THE PHYSICS PROGRAMS
VIII. PERFORMING EXPERIMENTS WITH THE MICROPHONE
  IX. GENERAL DESCRIPTION OF THE TIMER PROGRAMS
   X. OVERVIEW OF EACH PROGRAM 
  XI. PROGRAM DESIGN NOTES 

I. OVERVIEW 

This document describes the use of two sets of programs that help 
you perform experiments with a TI graphing calculator and the TI 
Calculator-Based Laboratory (CBL) System with Vernier sensors 
commonly used in physics. The PHYSICS set of programs support the 
motion detector and analog sensors, i.e. force sensor, 
accelerometer, microphone, and etc. The TIMER programs support 
photogates and Smart Pulleys.

With the PHYSICS set of programs you will be able to use a motion 
detector, force sensors, accelerometers, microphones, pressure 
sensors, temperature probes, light sensors, voltage leads, 
current probes, etc. Data collection modes can be used to 1) 
monitor CBL channels, 2) collect data as a function of time, 3) 
collect data with a manually-entered independent variable, and 4) 
collect data using the trigger button on the CBL. Time graphs 
generated in real time are possible but this option only works 
when one or more of the same probe are active. If the active 
probe is the Motion Detector, a live graph of distance vs. time 
is drawn and neither velocity nor acceleration data will be 
calculated. When more than one different sensor is active or when 
you want distance, velocity and acceleration from the Motion 
Detector, the time graphs will be displayed after the data is 
collected. When the Motion Detector is used in conjunction with 
the other sensors, only two of these probes can be active. This 
occurs because the TI-82 is limited to six lists and the motion 
data uses four lists. The programs on the other calculators are 
prevented from using more than 3 probes to keep the programs 
consistent. One of the features of the calculator is the ability 
to model data with different regression models. In working with 
real data, it is helpful to select a region of data with which to 
work. Since the calculator applies the regression models to the 
entire list, the calculated fit may be affected by unwanted data. 
With this program it is possible to select a region of the graph 
and automatically delete unwanted data outside the region of 
interest for each of the data lists.

The TIMER set of programs support Vernier Software Photogates, 
PASCO Photogates and PASCO Smart Pulleys in three different modes 
of operation. The photogates and Smart Pulley require an adapter 
(order code CBL-P for a single photogate or CBL-2P for two 
photogates) available from Vernier Software. Note: These programs 
will not work with the TI light probe.

II. MEMORY REQUIREMENTS

It is possible that you may run into "memory error" problems when 
using these sets of programs. These errors may occur for two 
reasons. 

1) This entire set of programs will require a considerable amount 
of the available memory on the calculator.
2) If you use a motion detector in combination with other probes, 
large amounts of data may be collected.

If you run into memory errors, you may have to collect less data 
or you may have to free up calculator memory by deleting lists, 
matrices, pictures and/or programs. If there are certain data 
collection modes in PHYSICS you are not using e.g. trigger, you 
can delete programs associated with these modes-PHZTRIGG in this 
example. (You will find a description of each program later in 
this document.) You may also want to consider deleting the 
PHZMICRO program if you are not going to use the microphone. If 
you are not going to be using photogates, you can delete TIMER 
and all the sub-programs that begin with TM. If you aren't going 
to be using the PHYSICS part of the program, you can delete 
PHYSICS and all the sub-programs that begin with PHZ. Refer to 
your calculator manual for specific information on deleting 
programs. 

If you reset your calculator, then load the PHYSICST group file 
(or PHYSICS on the TI-85) group file, the maximum number of 
points you can collect with two probes and a motion detector on 
the TI-82 is 99, the TI-83 120, the TI-85 55, the TI-86 512, and 
the TI-92 190.

III. GROUP FILES

The PHYSICST group file is thirteen programs that have been 
grouped together. Groups of files for the TI calculator always 
have a "??g" suffix where "??" represents the various 
calculators: 82, 83, 85, 86, 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 thirteen 
programs on to your calculator is to transfer the PHYSICST.??g 
group file. Note: On the TI-85, all the programs will not fit on 
the calculator at the same time, therefore there are two group 
files, PHYSICS.85g with the physics parts of the program, and 
PHOTGATE.85g with the photogate parts of program.

IV. SENDING GROUP FILES

You will need to use TI-Graph Link to send the PHYSICST.??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 PHYSICST.??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 thirteen programs available: 
PHYSICS, PHZCALIB, PHZCALS, PHZGRAPH, PHZMICRO, PHZMONIT, 
PHZOPTIO, PHZTIMEG, PHZTRIGG, TIMER, TMGTSTAT, TMMOTION, TMGATE, 
TMPENDLM, and TMPULSE. The TI-GRAPH LINK will also allow you to 
download all thirteen 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. GENERAL DESCRIPTION OF THE PHYSICS SET OF PROGRAMS 
 
The PHYSICS program and its eight sub-programs (PHZCALIB, 
PHZCALS, PHZGRAPH, PHZMICRO, PHZMONIT, PHZOPTIO, PHZTIMEG, 
PHZTRIGG) programs function together to provide a wide range of 
options as you create and run experiments. To begin, run the 
PHYSICS program. You do not need to run the sub-programs because 
PHYSICS calls them when necessary. The PHYSICS program uses a 
series of menus allowing you to set up different types of 
experiments with a combination of probes.
 
The following general description applies to the use of these 
programs on your calculator. For specific help in executing 
programs on the calculator, refer to the manual. To begin, run 
the PHYSICS program. After an introductory screen, the following 
MAIN MENU will appear: 
 
***MAIN MENU***
1:SET UP PROBES 
2:COLLECT DATA 
3:VIEW GRAPH
4:RETRIEVE DATA
5:OPTIONS
6: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 
GRAPH=VIEW GRAPH
RETRI=RETRIEVE DATA
MORE =MORE

The MORE option will bring up this menu:

OPTIO=OPTIONS
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 CBL provides access to three analog channels, channels 1 - 3, 
for devices such as force sensors, accelerometers, and 
temperature probes. One sonic channel is available for an 
ultrasonic motion detector. When you choose the first option, SET 
UP PROBES, from the above menu, you will be able to 1) enter the 
number of active probes, 2) choose a probe, 3) enter the CBL 
channel number for any analog device, and 4) choose the method of 
calibrating analog probes. If you are using a Motion Detector, 
you will not be prompted for a channel number since the Motion 
Detector will only work in the sonic channel. As you connect 
analog probes to the CBL, connect each to the lowest available 
channel. The program will limit the number of analog devices to 
two when you are also using the Motion Detector. 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:MOTION
2:FORCE
3:ACCELEROMETER
4:MICROPHONE
5:PRESSURE
6:TEMPERATURE
7:MORE PROBES

The first option represents the Vernier Motion Detector. The 
second option will bring up a menu from which you can choose the 
Vernier Student Force Sensor, the Vernier Dual Range Force 
Sensor, or the PASCO Force Sensor. The third option brings up a 
menu from which you can choose the Low-g or 25-g Accelerometer. 
The fourth option works with the CBL, MPLI, or ULI microphone. 
(When you select this option, you will be sent to a subprogram to 
collect data. This program is explained later.) The fifth option 
represents the Pressure Sensor and the sixth option is used for 
the TI Temperature Probe or the Vernier Direct-Connect 
Temperature probe. Selecting Option 7 produces this list of 
probes:

SELECT PROBE
1:LIGHT
2:MAGNETIC FIELD
3:VOLTAGE
4:C-V CURRENT
5:C-V VOLTAGE
6:THERMOCOUPLE
7:MORE PROBES

The first option can be used for either the TI Light Probe or the 
Vernier Light Sensor. The second option represents the Magnetic 
Field Sensor. The third option is used for either the TI Voltage 
probe or the Vernier Voltage Leads. The fourth is used with the 
Current and Voltage System Current Probe while the fifth option 
represents the Current and Voltage System Voltage Probe. The 
sixth option is used with the Thermocouple. Selecting Option 7 
produces a final list of probes.

SELECT PROBE
1:VERN STD TEMP
2:VERN QIK TEMP
3:PHOTOGATE
4:RETURN

The first option refers to the Vernier Standard Temperature Probe 
while the second option refers to the Vernier Quick-Response 
Temperature Probe. The third option will take you to the TIMER 
program which allows you to use photogates and Smart Pulleys with 
the CBL. Option 4 returns you to the first list of probes.

The above lists will appear up to three times depending upon the 
number of probes you entered. After you select an analog probe, 
you will be asked to enter the channel number for that probe. 
After you enter the channel number, you will be presented with 
the following CALIBRATION menu:

**CALIBRATION** 
1:USE STORED
2:PERFORM NEW
3:MANUAL ENTRY

The first option, USE STORED, in the above menu allows you to 
load standard slope and intercept values for Vernier probes. 
These are "generic" slope and intercept values determined by 
Vernier Software. The values will provide reasonably accurate 
measurements but individual probes differ and you may obtain 
better results by performing a new calibration. (The PHZCALS 
program contains the Vernier standard slope and intercept values. 
It is possible to edit this program and enter the slope and 
intercept values for your probes.) 

If you choose to perform a new calibration, it is helpful to 
understand the operation of Vernier probes other than the Motion 
Detector. During their operation, the probes produce a voltage 
that is linearly dependent upon a physical quantity. For example, 
the Student Force Sensor produces a voltage that varies linearly 
with the applied force. During the calibration process, the 
computer establishes the linear relationship between voltage and 
force. 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 
Student Force Sensor. The same general procedure can apply to the 
any analog sensor.

After you choose the PERFORM NEW option from the above menu, 
remove all forces from the Force Sensor. Monitor the CBL display 
for 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. You 
are then prompted to enter the reference value, 0 newtons in this 
case. Apply a known force to the sensor as a second reference. 
The easiest method is to hang a labeled mass from the beam end of 
the sensor. For example, a 200-g mass weighs 1.96 N. The voltage 
is again monitored and the [TRIGGER] button is pressed when the 
voltage stabilizes. Enter the second reference value. A slope and 
intercept for the linear calibration curve are then displayed on 
the calculator and 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 further 
help with other sensors and probes refer to the information sheet 
for those devices.

Option 3, MANUAL ENTRY, in the Calibrate Menu is an option that 
may save you time in setting up future experiments especially if 
you have performed calibrations for your probes. Probes such as 
the Force Sensor 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.

After the channels and probes are set up, you will return to the 
MAIN MENU. 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:RETURN 

The MONITOR INPUT option is used to monitor the active channels 
with the calculator. The purpose of this option is to view data 
at approximately 1.0 second intervals. No data is stored. For all 
probe combinations, each active channel will be displayed on the 
calculator. When done monitoring the channels, press the [+] key 
on the calculator to quit.

The TIME GRAPH option from the DATA COLLECTION menu is used to 
collect data as a function of time. A screen will prompt you to 
enter the time between samples which is entered in seconds. The 
sample time can be in the following range of values: 0.000164 to 
0.2 seconds or 0.25 to 16000 seconds. However, the minimum sample 
time depends upon the number and types of active probes and the 
data collection mode.

If you plan to use a live display where a graph is shown during 
data collection and you only have one probe, the minimum sample 
time is 0.1 s regardless of the type of probe. (If you enter a 
time less than 0.1 seconds, you will not get a live display.) If 
you enter a value between 0.1 s and 0.2 s and you use a live 
display, the CBL will collect data at 0.1 s. If you have two 
similar probes, the minimum sample time for a live display is 1 
s. If you have three similar probes, the minimum sample time for 
a live display is 1.25 s.

If you are going to collect data without a live display, the 
minimum sample time for one analog probe is 0.000164 s. For two 
analog probes the minimum time is 0.000264 and for three probes 
it is 0.000364 s. The minimum sample time for the Motion Detector 
with a non-live display is 0.008 s. (The minimum sample time will 
increase by 0.0006 s if you use the manual trigger option, a 
feature available in the OPTIONS menu.) If you enter a value less 
than the minimum sample time, the calculator will use the minimum 
sample time allowed for your setup. To automatically collect data 
at the minimum sample time, enter 0 as the sample time.

After the sample time is entered, you will be prompted to enter 
the number of data points. The maximum number on the TI-82 is 99, 
on the other calculators it is 512, although you may be limited 
by available memory. (See Section II for Memory Requirements.)

Under certain conditions (detailed below) the following menu will 
appear allowing you to choose between live and non-live displays:

COLLECTION MODE
1:NON-LIVE DISPL
2:LIVE DISPLAY 

This menu will appear under these conditions:
1) only one type of probe is active,
2) triggering is not being used to start data collection,
3) the sample time is greater than or equal to the minimum value 
for a live display, and 
4) the sample time is less than 270 s (4.5 minutes). 

The NON-LIVE DISPL option will collect data without displaying a 
graph during data collection. This option provides the greatest 
flexibility in designing experiments by permitting combinations 
of probes, triggering, and a wider range of sample times. (If you 
did not see the above menu, the data will be collected without a 
live display.) If the Motion Detector is active, only two analog 
channels can be active. If you are only using analog channels, 
you will see graphs of each channel when data collection is 
complete. If the Motion Detector is the only active channel, then 
you will be able to choose from three graphs: distance vs. time, 
velocity vs. time, and acceleration vs. time. If you are using 
the Motion Detector and analog probes, you will be able to choose 
between the different analog channels and the different motion 
data.

The LIVE DISPLAY option produces a "real-time" graph during data 
collection. However, this option will only work with probes of 
the same type and if the sample time is less than or equal to 270 
seconds. Please note that the time base during data collection 
with a live display is only approximate. To record an accurate 
time base, use the Non-Live Display option.

If the experiment is longer than 270 seconds (4.5 minutes) and 
non-live or you are using a manual trigger, the experiment is 
considered to be a long-term experiment since the calculator will 
automatically power down. A message will direct you to use the 
RETRIEVE DATA option from the MAIN MENU. Select this option after 
the data collection is complete when the CBL display shows 
"DONE". After the option is chosen, the data will be retrieved 
from the CBL and the graph or graphs will be displayed. 

Each time you view a graph, you will be able to read off the 
coordinates of each data point. The coordinates of the first 
point will be displayed on the bottom of the screen. To view 
other points use the left and right arrow buttons on the 
calculator to move across the screen.

The TRIGGER/PROMPT option in the DATA COLLECTION menu 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 Light Sensor to measure the light intensity as the distance 
from the source changes. When the [TRIGGER] button on the CBL is 
pressed, the CBL measures the light intensity and you will be 
prompted to enter the distance from the source.

After you select this option, a screen will appear prompting you 
to press the CBL [TRIGGER] button when you are ready to take a 
sample. You will then be prompted to enter the independent 
variable. The following menu then appears:

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 in the DATA COLLECTION menu is used to 
manually sample each active channel when the [TRIGGER] button on 
the CBL is pressed. (In this data-collection mode, you do not 
enter an independent variable as done in the TRIGGER/PROMPT 
mode.) Each time you press the [TRIGGER] button, you will get the 
following screen:

TRIGGER
1:CONTINUE
2:STOP
3:PAUSE

If you select option 1:CONTINUE, the CBL will be set up to make 
another reading. If you select option 2:STOP, data collection 
will stop and you will return to the MAIN MENU unless there are 
two active probes in which case a graph will be drawn. 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. 

During the data collection process in the TRIGGER/PROMPT and 
TRIGGER modes you can monitor each active channel by pressing and 
holding the [CH VIEW] button on the CBL. Repeated pressing of 
this button will cycle you through the active channels.

The third option, VIEW GRAPH, on the MAIN MENU allows you to 
review previously set up 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 on the MAIN MENU, RETRIEVE DATA, is used after 
data is collected during a long-term experiment. Before you 
select this option, be sure the CBL is done collecting data. (The 
word "DONE" should appear in the CBL display.)

The fifth option, OPTIONS, in the MAIN MENU brings up this menu:

PHYSICS OPTIONS
1:SELECT REGION
2:INTEGRATE
3:MANUAL TRIGGER
4:TRIGGERING
5:ZERO SENSOR
6:RETURN

The first option SELECT REGION is used to select a portion of 
data. This feature is helpful in deleting extraneous data thereby 
making it easier to model data. After this option is selected, a 
menu will appear asking you which graph you wish to examine. This 
graph will then be displayed so that you may select a region of 
data. Use the arrow keys to move the cursor and select the lower 
limit of the region and press [ENTER]. A horizontal line will be 
drawn on the graph. Now move the cursor to select the upper limit 
and press [ENTER]. Data above and below these limits will be 
deleted from ALL lists.

The second option, INTEGRATE, is used to integrate a section of 
the graph. After selecting this option, choose a graph from the 
list displayed on the screen that follows. Use the arrow keys to 
move the cursor and select the lower limit of the region and 
press [ENTER]. A horizontal line will be drawn on the graph. Now 
move the cursor to select the upper limit and press [ENTER]. 
After the integration is performed, vertical lines will be drawn 
to represent the integrated area. Press [ENTER] to see the 
numerical results.

The third option, MANUAL TRIGGER, will bring up a menu asking you 
if you wish to use a manual trigger. When you are performing a 
time graph experiment with a manual trigger, the data will not be 
collected until you press the [TRIGGER] button on the CBL. This 
is helpful when you want to collect data while the CBL is 
disconnected from the calculator. You can reconnect the 
calculator to the CBL and use the RETRIEVE DATA option to 
retrieve the data from the CBL, and then analyze the data on the 
calculator. You should use this option after you have set up the 
probes. If you set up probes after selecting this option, the CBL 
will trigger automatically.

The fourth option, TRIGGERING, will set up the CBL to begin 
collecting data when the signal from Channel 1 or 2 reaches a 
certain value. You can trigger on any analog probe except the TI 
temperature probe. After selecting this option, you will choose 
the trigger channel. Next you will choose whether the measurement 
is rising or falling. You will then enter the trigger value and 
the amount of prestore data. This amount can be an integer 
between 0 and 100. You should use this option after you have set 
up the probes. If you set up probes after selecting this option, 
the CBL will not wait for the trigger.

The fifth option, ZERO SENSOR, will bring up this menu:

SELECT CHANNEL
1:CHANNEL 1
2:CHANNEL 2
3:CHANNEL 3
4:MOTION
5:ALL CHANNELS

When you zero an analog probe, it acts like a tare button. When 
you zero the motion detector, the measurements are made from a 
reference point. Objects that are closer to the Motion Detector 
than this reference point will be positive, things that are 
farther away than this will be negative distances. If you select 
option 5, ALL CHANNELS, all active probes will be zeroed. You 
should use this option after you have set up the probes. If you 
set up probes after selecting this option, the probes will use 
the calibration you set them up to use.

The sixth option, RETURN, will return you to the main menu.

The sixth option in the MAIN MENU, QUIT, will exit the program.

DATA STORAGE 

During data collection data is stored in the following lists:

time or independent variable in L1 

motion detector
     distance in L4
     velocity in L5 
     acceleration in L6

analog channels 
     channel 1 in L2
     channel 2 in L3
     channel 3 in L4

During the data collection process you can monitor each active 
channel by pressing and holding the [CH VIEW] button on the CBL. 
Repeated pressing of this button will cycle you through the 
active channels.


VIII. PERFORMING EXPERIMENTS WITH THE MICROPHONE

When you select the Microphone from the list of probes during 
probe setup, a separate program will be run. The primary use of 
this program is to produce waveform graphs of sound pressure as a 
function of time. If you are using a CBL or MPLI Microphone you 
will be able to monitor the frequency of a sound signal.

If waveform data is collected, it is possible to model the data 
with a trigonometric function. The program defines equation Y1 
with an appropriate form. 

We have found that the best waveforms occur when the peak voltage 
from the microphone is in the range of 0.5 to 1.0 volts. If the 
signal is much smaller than that, the quality of the waveform 
decreases. If this is the case, you may need to produce a louder 
sound or move the source closer to the microphone. When the 
waveforms are displayed by this program, you can use the arrow 
buttons to trace the waveform and check the voltage of the signal 
noting the maximum or minimum y values.

After choosing Microphone from the list of probes, a screen will 
appear reminding you to connect the microphone to Channel 1. The 
following screen will appear next and you will have to choose the 
type of microphone you are using.

SELECT MICROPHN
1:CBL
2:ULI
3:MPLI

The next screen provides a list of data collection modes.

COLLECTION MODE
1:WAVEFORM
2:WAVEFORM/TRIGR
2:FREQUENCY 
3:RETURN 

If you choose Option 1, WAVEFORMS, a screen will appear prompting 
you to hold a sound source close to the microphone. After you 
press the [ENTER] key on the calculator, the CBL will quickly 
sample the sound source. A display of sound pressure vs. time 
will be displayed on the calculator and you can use the arrow 
keys to trace data points on the graph. After you press [ENTER] 
from the graph screen, you will be asked whether you want to 
repeat the data collection. If not, you will return to the MAIN 
MENU. During sampling the time is stored in list L1 and voltage 
which is proportional to sound level is stored in list L2.

Option 2, WAVEFORM/TRIGR, also produces a waveform but this time 
the CBL is placed in a trigger mode. The CBL will not start to 
collect data until the voltage reaches 0.2 V. (Note: this mode 
will only work with the CBL or MPLI microphone.) Once the trigger 
occurs, sampling begins and a graph of sound pressure vs. time 
will be displayed. After you select this option, a screen will 
prompt you to press [ENTER] to make the CBL ready. The CBL will 
then wait for a trigger. After the data is collected, the graph 
will be displayed and you can use the arrow keys to trace the 
data points on the graph. Again the time is stored in L1 and 
sound level is stored in list L2.

Option 3, FREQUENCY, in the MAIN MENU will monitor a sound source 
held near the microphone and display its frequency in hertz. 
(Note: this mode will only work with the CBL or MPLI microphone.) 
After you select the option, you will be instructed to press the 
[ENTER] key to prepare the CBL to collect data. The next screen 
will prompt you to hold a sound source close to the microphone. 
When the sound intensity reaches a certain level, the CBL will be 
triggered and the signal will be monitored. If the sound is weak, 
you may have to hold the source very close to the microphone. 
After a short time, the frequency will be displayed on the 
calculator. The frequency will be stored in list L1. After you 
press [ENTER], you will be given the opportunity to repeat the 
data collection.

EDITING THE TIME BETWEEN SAMPLES

When waveforms are collected, this program is set up to collect 
data as fast as possible. The minimum sample time in this 
situation is 0.000165 s. You may want to change this value. This 
is done by editing the Sample and Trigger Command (command 3) in 
the PHZMICRO program. If you are collecting waveforms using 
Option 1:WAVEFORMS, locate this command, 
{3,0.000165,99,0,0,0,0,0,1,0}->L6 within the Lbl 1 section. If 
you are collecting waveforms using Option 2:WAVEFORM/TRIGR, 
locate this command {3,0.000165,99,2,1,.2,0,0,1,0}->L6, within 
Lbl 2 section. To increase the time between samples, edit the 
second number in these commands. For help in editing programs, 
refer to the guidebook that came with the calculator.

IX. GENERAL DESCRIPTION OF THE TIMER PROGRAMS

The following general description applies to the use of the TIMER 
set of programs on the calculator. For specific help in executing 
programs on the calculator, refer to the manual. To begin, run 
the TIMER program. After an introductory screen, the following 
main menu will appear: 

PHOTOGATE TIMING 
1:TIMING MODES 
2:CHECK GATE 
3:QUIT 
 
The first option, TIMING MODES, allows you to select different 
methods for using photogates and photogate/pulley systems. The 
next section describes this option. The second option, CHECK 
GATES, provides a check of the photogate. Choosing this option 
brings up a screen that displays the status of the photogate. 
Slowly move an object through the photogate to verify that it 
changes between the blocked and unblocked states. The third 
option, QUIT, returns you to the Home Screen where you have 
access to graphing and statistical analysis features. 
 
After checking to see that the photogate works, select the TIMING 
MODES option and the following menu will appear: 
 
**TIMING MODES** 
1:MOTION 
2:GATE 
3:PENDULUM 
4:PULSE
5:RETURN 
 
The first option, MOTION, allows you to use photogates and 
photogate/pulley systems to collect data and view graphs of 
distance, velocity and acceleration as a function of time. The 
second option, SINGLE GATE, records the time that a photogate is 
blocked. The PENDULUM option measures the period of a pendulum as 
it travels back and forth through a photogate. Each of these 
modes is described below. 
 
When you select MOTION from the TIMING MODES menu, the following 
menu appears: 
 
*MOTION TIMING* 
1:SELECT DEVICE 
2:COLLECT DATA 
3:VIEW GRAPHS 
4:REPEAT 
5:RETURN 
 
The SELECT DEVICE option will produce another menu from which you 
will choose an appropriate photogate device. The options are: 
 
SELECT DEVICE 
1:VERNIER PICKET 
2:SMART PULLEY 
3:CUSTOM DEVICE 
4:RETURN 
 
The VERNIER PICKET is a picket fence containing eight opaque bars 
separated by seven clear bars. The distance between the leading 
edges of the opaque bars is 0.05 m. Selecting the SMART PULLEY 
option brings up a list of various photogate/pulley arrangements.

SMART PULLEY 
1:10 SPOKE INSID 
2:10 SPOKE OUTSI 
3:3 SPOKE INSIDE 
4:3 SPOKE OUTSID 

These options refer to two different PASCO Smart Pulleys 
(containing either three or ten spokes) operating in two 
different modes. In one mode a string is pulled through the 
groove in the pulley. In the other mode the pulley is spun by an 
object on the outside edge of the pulley. 

If you choose the CUSTOM DEVICE option in the SELECT DEVICE menu, 
you will be asked to enter the number of opaque objects in the 
picket fence or bar tape and the distance between leading edges. 
 
After the device has been chosen, you will return to the MOTION 
TIMING menu where you can now begin to collect data. If you have 
selected a photogate/pulley, you will be asked to estimate the 
number of revolutions. This estimate will tell the CBL when to 
stop collecting data. Since the TI-82 calculator is limited to 99 
elements in a list, you will be limited to the number of 
rotations of the pulley. You may have to design your experiment 
with this in mind if you are using the TI-82, the other 
calculators are limited to 512 points.

After the data is collected you will have a chance to view 
distance vs. time, velocity vs. time, and acceleration vs. time 
graphs. As you view the graph, you will also be able to use the 
left and right arrows to read off the coordinates of each data 
point. After viewing these graphs, you will then have an 
opportunity to repeat the experiment or return to TIMING MODES 
menu. You can then return to the main PHOTOGATE TIMING menu. 

Option two, GATE, in the TIMING MODES menu will measure the time 
during which one or two photogates are blocked. After you select 
this option, you will have to choose whether you are using one or 
two gates. Then you will be directed to move an object through 
the photogate to arm the gate. The CBL will now record the time 
or times as the next object passes through the photogate(s).

Option three, PENDULUM, in the TIMING MODES menu will measure the 
period of an object as it oscillates through the photogate. You 
will be asked to enter the number of oscillations. The CBL will 
measure the period of this motion and report the average.

Option four, PULSE, measures the time between two blocking 
events. If you are using one photogate, the timer starts when the 
photogate is first blocked, and it stops when the photogate is 
blocked again. When two photogates are used, you can time from 
the blocking of the first gate to the blocking of the second 
gate.
 
CALCULATOR LISTS 
 
When you choose the MOTION option in the MOTION TIMING menu, 
pertinent data is stored in lists on the calculator. The 
following summarizes the arrangement: 
 
L1 - time
L2 - distance 
L3 - velocity 
L4 - acceleration

X.OVERVIEW OF EACH PROGRAM 
 
A. The PHYSICS program will call the other programs depending 
upon the options you choose. Each program is briefly described 
below. 

PHYSICS - This is the main program that controls the set up of 
the probes and the experiment. Begin by running this program. 

PHZCALIB - This calibration program provides three options 
allowing you to: 1) to use a default calibration, 2) perform a 
new calibration, and 3) manually enter the slope and intercept 
for a known calibration. For specific help in performing a new 
calibration, refer to the information sheet that came with each 
sensor. 

PHZCALS - This file contains the intercept and slope values for 
each Vernier analog probe. You can edit this file with the 
calibrations of your set of probes.

PHZGRAPH - This program performs various graphing functions.

PHZMICRO - This program is called when you select the Microphone 
from the list of probes.

PHZMONIT - This program is called when you want to monitor the 
readings from one or more channels. 

PHZOPTIO - This program is used to select regions of data, 
determine integrals, and set experiment triggering.

PHZTIMEG - This program produces graphs of active channels as a 
function of time. If only one probe is active, a real time graph 
can be displayed on the calculator as the data is collected. If 
more than one channel is active, a real time graph will not be 
available. You will have to wait until the data collection is 
done in order to see the graphs.

PHZTRIGG - This program supports the trigger/prompt and trigger 
data collection modes. Each time you press the [TRIGGER] button 
data is stored in the CBL. In the trigger/prompt mode you will be 
prompted for an independent variable. In the trigger mode, you 
will not be prompted for a variable.

B. The TIMER program will call the other programs depending upon 
the options you choose. Each program is briefly described below.

TIMER - This is the main program that calls the subprograms. Run 
this program to begin.

TMGTSTAT - This program checks the status of the photogate and 
reports whether the gate is blocked or unblocked. Move an object 
slowly through the gate to see is the gate status changes between 
blocked and unblocked.

TMMOTION - This program uses picket fences, bar tapes and 
photogate/pulley systems to collect distance, velocity, and 
acceleration data.

TMGATE - This program measures the time that a photogate or two 
photogates are blocked.

TMPENDLM - This program determines the period of an object as it 
oscillates through a photogate.

TMPULSE - This program measures the time elapsed as an object 
travels between two photogates or the time as an object moves 
through the same photogate twice.

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 programs with other teachers and students. 
Hopefully they have been written in such a way that you can 
modify them for your particular application. 
 
The programs were designed and written by Rick Sorensen and 
Matthew Denton. Please contact us if you have any questions 
concerning these programs or the use of our probes with the 
programs. 


March 27, 1998

Rick Sorensen (rsorensen@vernier.com)
Vernier Software 
8565 S.W. Beaverton-Hillsdale Hwy. 
Portland, OR 97225-2429 
phone: (503) 297-5317 
fax:   (503) 297-1760
http:\\www.vernier.com