TSIP Output

The Lassen LP GPS receiver module is configured to automatically output the following packets. For minimal system implementations, these output packets provide all of the information required for operation including time, position, velocity, receiver and satellite status, and health. Position and velocity are reported using one or more of the packets listed below, depending on the selected I/O options. While there are other packets automatically output, the following packets provide the information most commonly used. No input packets are required. The receiver automatically outputs position and velocity reports at set intervals. Automatic report packets are controlled by Packet 35. Setting the control bits as indicated in the table below allows you to control which position and velocity packets are output. A complete list of program commands can be found in the Help Manual. The help manual is very helpful.

The TSIP output covers almost anything one would need to know, including: synchronized measurement packet, auto velocity fix (ENU), auto information about last computed fix, GPS system data/acknowledge, enable/disable & health, raw measurement data, satellite tracking status, all-in-view satellite selection auto, differential position fix mode auto, double-precision XYZ auto, double-precision LLA auto, differential correction status, last fix with extra information (fixed point) auto, UTM auto, graceful power down status, low power mode, and low power configuration. TSIP has the most options, which has been said time, and time again, but it is also very hard to understand.

Hyperterminal Introduction

To see an example of this, find the hyperterminal program on your computer. Click Start, Programs, Accessories, Communications, and then it should be right there. This program reads the information right off of the serial line, which is the cable that plugs directly into your computer. When you open the program, it will ask you for a name. This doesn't matter. Whatever you want to type in is fine. After hitting OK, the next option you get is one to connect to which COM port. You should see a "Connect Using: " message at the bottom of the option list. Scroll down the list of options until you reach "Direct to COM 1/2/3/4" depending on which COM port your computer is using. Then hit OK. The baud rate should be what you set it to earlier in the TSIPCHAT program. I personally use 9600. Everything else should remain the same. The message you receive looks like giberish. There are ways to translate it, but I decided that either TAIP or NMEA might be more useful in this particular instance. Both consist of ASCII, and NMEA is standard everywhere. To see more on how to configure the output of TAIP or NMEA, scroll down.

TAIP Output

TAIP is the second language offered in the GPS unit. It has many advantages, most of which deal with its uncomplicated look. The see the TAIP output, simply use hyperterminal as seen above, after setting the output language to TAIP in TSIPCHAT. What you should see is a set of three numbers, which at first seem like giberish. However, it is actually listing the altitude, longitude, and latitude. The decimal point is missing, however, so you have to read it as if there is one. It is in place two places after the start of the number. At Drexel University, in the Micro Air-Vehicle Lab, the 39 degrees, 57.271 minutes north, and 75 degrees, 11.139 minutes west. The altitude is about 7.6 meters above sea level. I would see all those numbers, only without the decimal places.

TAIP offers the least customizable options however. It offers little more than altitude, longitude, and latitude. It can be changed to offer ground velocity too, however. It just lacks the completeness of TSIP.

NMEA 0183 Output

NMEA 0183 is almost a hybrid between TAIP and TSIP. It combines the easy readability of TAIP with the plethora of options of TSIP. NMEA is written in ASCII, and although the format is more difficult to understand, it has numbers instead of seemingly random characters. One can ask the GPS for UTC of Position, latitude, longitude, GPS quality indicator, number of satellites in use, HDOP, antenna altitude in meters, GPS fix data, GPS DOP and active satellites, GPS satellites in view, ground speed, and time and date. All these options can be configured in TSIPCHAT with little trouble. To see how the language works, simply follow the instructions above with hyperterminal.