The AUX port and the Impulse Laser Rangefinder
Unfortunately, often the solution to iPAQ problems is a soft reboot. This requires removing the iPAQ from its case, if it is in one, and pressing the tip of the stylus into the hole on the base of the iPAQ to the right side of the serial port. A red and white screen will follow, and then the iPAQ will reboot. As discussed in greater detail below, unless you have a data collection form open in ArcPad at the time of the soft reboot, you will not lose any data that you have collected.
The GPS (top)
Using the GPS Position Window.
Not receiving data from the GPS. Check cables and connections.
Expansion pack initialization failed. See manufacturer’s instructions.
Turning off GPS error messages.
Setting the GPS COM Port and data protocol.
Using the external antenna with the Crux CompactFlash GPS card.
What is the accuracy and precision of the Crux CompactFlash GPS card?
Simple troubleshooting of the GPS.
Advanced troubleshooting of the GPS card.
The AUX port
and the Impulse Laser Rangefinder (top)
Setting up the AUX port for the Impulse Laser Rangefinder.
Can the Laser Rangefinder be wireless?
Using the Laser Rangefinder and a GPS receiver.
Peripherals (top)
The scanner is plugged in and there are messages for .DLL files.
Can’t print to the printer Canon BJC-85 anymore.
Software (top)
Most of the software FAQs are better answered as help pages, and are available here. Below are a couple easy, quick, questions.
Save the Map in ArcPad and saving field data.
Can’t transfer files between the iPAQ and the laptop.
The data collection forms in ArcPad are frozen.
The CompactFlash
GPS Card
Using the GPS Position
Window. (top)
The ArcPad GPS window can be accessed by pushing the GPS icon on the main ArcPad toolbar. The GPS Window looks like this:
The
top two lines show the X and Y position recorded by the GPS receiver. Tapping this position with the stylus opens a
menu with variety of options for displaying the position information, such as
decimal degrees, UTM, military grid, etc.
The type of positioning information is given by the ‘3D’. Possible types are 2D, 3D, and DGPS 3D, which
is enabled when a WAAS signal is available. The current GPS elevation is given to the
right, here 856 m. Tapping the elevation
allows toggling between statute and metric units. The radial diagram to the lower right of the
window shows the GPS satellite sky view.
Black numbered squares are satellites used for position fixes. Red squares are satellites not currently
locked for positioning. Blue squares
(not shown) are satellites in the process of being acquired. Other abbreviations for GPS information are
SOG (speed over ground), and TCOG (true course over ground) for navigation, DST
(distance) and BRG (bearing) for waypoint tracking, and error estimation, here
shown as PDOP (position dilution of precision).
Tapping PDOP displays a menu which a variety of options for estimating
error in positioning.
What is WAAS? (top)
WAAS stands for Wide Area Augmentation
System, and is a real time differential GPS correction provided by the FAA
to navigate aircraft in the
No current fix available. (top)
The GPS receiver connected to ArcPad has not fixed enough satellites to provide GPS positioning information. If you have just activated the GPS in a new area, acquiring adequate satellite for positioning can take up to 20 minutes. If you are re-activating the GPS in an area where you have been working, this message should disappear in only a few minutes.
Not receiving data from GPS. Check cables and connections. (top)
The first thing to check if this error is encountered is the setting of the GPS COM port. If this is set correctly, then the next two connections to check are the CompactFlash GPS card connection and the CompactFlash expansion pack connection. If you are using an iPAQ in a ruggedized case, and a CF expansion pack without an external battery, then it is most likely that the GPS card is not connected properly, as it is a very tight fit in the top of the rugged case. Press down on the GPS card and make sure that it is well-seated in the expansion sleeve. If this does not work, or if you are using an expansion pack with a replaceable battery, then the expansion sleeve likely is disconnected from the iPAQ. Open the rugged case and seat the iPAQ firmly in the expansion sleeve. If a message flashes across the screen reading ‘Expansion pack initialization ….’, then this has likely solved the problem. If neither of these connections seem to be problematic, then re-connect everything firmly, perform a soft reboot and try again.
Expansion pack initialization failed. See manufacturer’s instructions. (top)
This message is fairly rare. In such a case, reconnect the iPAQ firmly to the expansion sleeve and perform a soft reboot.
Turning off error messages. (top)
Select the ‘Options’ palette from the ‘Tools’ menu on the Main ArcPad toolbar. Scroll through the pages until you find ‘Alerts’. Checkboxes allow you to toggle on or off audible and visible alerts, most pertaining to the status of the GPS.
Setting the GPS COM port and data protocol. (top)
Data protocol
Select the ‘Options’ palette from the ‘Tools’ menu on the Main ArcPad toolbar. Scroll through the pages until you find ‘Protocol’. If you want the GPS to activate automatically on the start of ArcPad, check ‘Automatically Activate’. If you are using anything other than a Trimble GPS receiver, the Protocol should be set to ‘NMEA 0183’. If you are using a Trimble, you can also use the TSIP protocol. The CompactFlash GPS receivers used with the iPAQs output GPS data in NMEA format. If you are using an external handheld GPS receiver, you may need to set the GPS receiver to output data in NMEA format.
COM port
Select the ‘Options’ palette from the ‘Tools’ menu on the Main ArcPad toolbar. Scroll through the pages until you find ‘GPS’.
Settings:
COM Port:
iPAQ with CompactFlash GPS Card
3700 and 3800 series iPAQs: COM 5
3900 series iPAQs: COM 6
Handheld GPS with Bluetooth wireless connection:
3700 and 3800 series with Bluetooth CF card: usually COM 7 or COM 8, set up
through Bluetooth software
3900 series with Bluetooth CF card: usually COM 7 or COM 8, set up
through Bluetooth software
3900 series with built-in Bluetooth: COM 4
Handheld GPS with serial cable connection:
All series of iPAQ: COM 1
Baud: 4800 (for CompactFlash GPS cards, the baud rate may vary using a handheld GPS with cabled or wireless connection).
Data bits: 8
Parity: None
Stop Bits: 1
RTS Control: enable
DTR Control: enable
All checkboxes unchecked.
Using the external antenna with the Crux CompactFlash GPS card. (top)
The Crux CompactFlash GPS card comes with an external magnetic antenna that can be mounted on a vehicle, or other metal object. The antenna has a small brass pin at the end of its cable which plugs into the top of the GPS card head. Some users claim faster satellite acquisition and better fixes with the external antenna. There have been some difficulties with the GPS cards when the external antennas have been plugged-in or unplugged during GPS use. To be safe, deactivate the GPS before adding or removing the external antenna, then reactivate it again.
What is the accuracy and precision of the Crux CompactFlash GPS card? (top)
The accuracy and precision of the Compact Flash GPS cards is largely dependent on the type of positioning available. Differential positioning via the WAAS system is significantly better than non-differential positioning. Positioning is also affected by satellite geometry, weather, and local topography. The following two charts give an idea of the repeatability of positioning fixes for the Crux CompactFlash GPS card versus a Garmin eTrex handheld GPS receiver. In both cases, the points were stored utilizing the TrackLog feature available in ArcPad. The Crux CompactFlash GPS card was attached to a model 3970 Compaq iPAQ, and the data was collected using an external antenna. The Garmin eTrex handheld GPS receiver was connected to a Winbook laptop computer via a serial port connection. The eTrex does not connect to an external antenna. 250 positioning fixes were recorded using each GPS receiver. The mean position was calculated, and the following graphs show horizontal and vertical deviations from the mean. (Caveat: the raw eTrex data appeared to be quantized. Deviations from the mean position occurred at discrete intervals, suggesting that position averaging may have occurred within the eTrex. No documentation was available to substantiate this. The Crux GPS data is not filtered or averaged, although such a feature is available within the ArcPad software).
Horizontal precision of the Crux CompactFlash GPS card and Garmin eTrex handheld GPS receiver
Vertical precision of the Crux CompactFlash GPS card and Garmin eTrex handheld GPS receiver
Although the scatter in the position estimates of the Crux GPS receiver looks substantial compared to the Garmin eTrex, a comparison of real world accuracy shows little difference between the two GPS units and real world data. The following graphic shows points recorded as discussed above using the Tracklog feature in ArcPad while driving on a series of dirt roads in the Spring Mountains, Nevada. The graphic illustrates the similarity in position fixes between the two units, as well as the accuracy of the units in locating the roads in real space. In the few places where there is substantial difference between the GPS units and the USGS DLG roads, the GPS units are in agreement, suggesting minor misplacement of the roads.
Accuracy of Crux and Garmin GPS in delineating digitized roads from USGS Digital Line Graphs
Simple troubleshooting of the GPS card. (top)
The easiest way to trouble shoot the CompactFlash GPS card if you are having difficulties is to check all of the connections, or to open the GPS positioning window to evaluate the status of the GPS fixes.
Advanced troubleshooting of the GPS card. (top)
More advanced troubleshooting can be attempted with the GPS Debug feature, available in the GPS menu on the Main ArcPad toolbar. Setting the debug mode displays the contents of the NMEA GPS data string on the screen. More details on the string are available in the ArcPad manual.
The AUX port and the Impulse Laser
Rangefinder
Setting up the AUX port for the Impulse Laser Rangefinder. (top)
The Impulse laser rangefinder can be connected to the iPAQ using either a cabled or a wireless solution. As discussed below, the wireless solution is not recommended. The cabled solution connects the Impulse Laser Rangefinder to the iPAQ through the serial port on the base of the iPAQ. To access the data from this port, the ‘AUX port’ settings must be configured. Select the ‘Options’ palette from the ‘Tools’ menu on the Main ArcPad toolbar. Scroll all the way to the right through the pages until you find ‘AUX’. Check that the following settings are configured:
Port: COM 1
Baud: 4800
Data bits: 8
Parity: None
Stop Bits: 1
RTS Control: enable
DTR Control: enable
All checkboxes unchecked.
What is a null modem? (top)
The cable that connects the Impulse Laser Rangefinder to the iPAQ consists of four separate pieces. First is the serial cable that transmits data from the Impulse. The Impulse Laser itself is connected to the Impulse MapStar Compass via a serial cable with proprietary fittings (circular with 4 pins). A second serial cable attaches to the MapStar compass. This cable has an Impulse proprietary fitting at one end and a standard 9-pin serial connection at the other. A serial cable is also necessary at the iPAQ end. This cable attaches to the iPAQ serial port using the iPAQ proprietary connector and also has a standard 9-pin serial connection at the other end. These cables can be purchased, if lost, from Impulse and Compaq/HP, respectively. Although these two cables will directly connect to one another, the pin order from the Impulse to the iPAQ needs to be switched. This is done with a 9-pin null modem adapter. This adapter can be picked up at any Radio Shack for a few dollars. Often the null modem adapter will cause gender difficulties (i.e. you will be left with two female or two male ends to connect after attaching the null modem adapter), so purchasing a 9-pin serial gender changer for a dollar or so can save a lot of hassle. Connect the null modem adapter to the Impulse serial cable, then the iPAQ serial cable to the null modem adapter, using the gender changer here as necessary.
Can the Laser Rangefinder be wireless? (top)
The short answer here is yes. The Digital Tools for Field Geology group have manufactured several Bluetooth wireless transceivers that can be attached to any serial cable to create a wireless serial replacement. In reality, however, the Bluetooth transceivers draw too much power, too quickly, from their 9 volt batteries. Batteries must be replaced frequently, and the wireless connection breaks often. The cost of batteries, and the tedium of re-establishing a wireless Bluetooth connection at this time make this an impractical way to connect the laser and the iPAQ.
Using the Laser Rangefinder and a GPS receiver. (top)
For a number of reasons, it may be desirable to use a GPS receiver simultaneously with the Impulse Laser Rangefinder. As suggested above, we strongly recommend using a cabled connection between the Impulse and the iPAQ. This connection requires that COM 1 be dedicated to the AUX port, and thus connecting a handheld GPS receiver at the same time as the Impulse is difficult. Our recommendation is to use a CompactFlash GPS card with the Impulse Laser Rangefinder. Other options are to use one of the Bluetooth wireless transceiver boxes with the handheld GPS (this appears to be less problematic with the GPS), or to investigate the possibility of adding a second serial port the iPAQ via a PCMCIA card adapter and PCMCIA expansion pack.
Laser Rangefinder Applets. (top)
The ArcPad software is not specifically designed to deal with data from the Impulse Laser Rangefinder (as opposed to the significant functionality built-in for GPS positioning). Laser data collected through the AUX port is useless without customized software to process it. Such code is available for certain applications via an ArcPad applet (see the software page). Additional functionality will need to be custom programmed.
Peripherals
The scanner is plugged in and there are messages for .DLL files. (top)
Windows 2000 (maybe XP?) seems to act funny about USB ports. The scanner software is installed on all of the fieldcamp laptops, however, the scanner will only work correctly when it is connected to the USB port that it was attached to when the software installation occurred. If you plug the scanner into a USB port and get nothing but error messages and requests for the location of .DLL files, plug the scanner into the other USB port. This should solve the problem.
Nothing is printing. (top)
Almost eleven months out of the year, the field camp computers are used at MIT for software development and course work, so the default printer is frequently set to an MIT network printer. If you are in the field, go to the Start Menu, Settings, and Printers, and set the Canon BJC-85 to be the default printer.
Can’t print to the printer Canon BJC-85 anymore. (top)
The Canon printer has a problem similar to the scanner, but slightly different. If the Canon printer is installed on one USB port, then later attached to the other, a copy of the printer is created entitled Canon BJC-85 (Copy 1). Continued USB port switching can propagate these copies, unfortunately, so try to keep the same printers plugged into the same ports on the same laptops.
Software (top)
Save the Map in ArcPad
and saving field data. (top)
Field data collected using ArcPad is automatically written to shapefiles and saved as soon as the ‘OK’ button is pressed on the top of a data collection form. The ‘Save map’ option under the File menu on the Main ArcPad toolbar saves local settings, which may also be of much use. For example, saving the map captures the current Zoom on the iPAQ screen and opens to that exact Zoom next time ArcPad is started. Saving the map also saves which layers are visible, and the symbology that the user has set for displaying the layers. If you have a layer called rivers.shp that you wish to always be drawn in blue, you would select the layer, change the draw symbology, then save the map. Without saving the map, the next time the map is opened, the rivers will be drawn with the default symbology.
Can’t transfer files between the iPAQ and the laptop. (top)
There are three general possibilities which lead to this problem. If you have recently removed some of the files from an archive CD, they may be set as Read-only. Right click on one of the files and select properties. If the Read-only box is checked, then uncheck it and click OK. You may have to do this for multiple files, or for an entire folder. Another possibility is that the file you wish to transfer (or a file of the same name) may be currently open either in ArcPad on the iPAQ or in ArcGIS on the laptop. In such a case, the files will not transfer. Quit ArcPad on the iPAQ or remove the file from the active ArcGIS map and the transfer should proceed. Lastly, if you are using one of the combination car charger/Sync/USB cables, the cord may be set to power instead of sync. Look for a small silver switch labeled at one end with a lightning bolt and the other with a double-arrowed circle. Make sure the switch is set to the double-arrowed circle, remove and replug the iPAQ and try again. If all of these fail, try a soft reboot on the iPAQ and sync again.
The data collection forms in ArcPad are frozen. (top)
The data collection forms,
particularly for geologic mapping, sometimes pop open a message box to confirm
that data has been added to the form.
Occasionally, due to a double-tap on the form or other anomaly, the
message box gets sent behind the data collection form without being
closed. This will freeze the data
collection form. Grab the top of the
data collection form and drag it to the bottom of the screen. Close any message boxes by clicking their ‘OK’
buttons. Bring the data collection form
back up onto the screen. If this does
not unlock the forms, you may have to soft reboot the
iPAQ. In such
a case, you will need to re-enter any data that was in the open form.