GPS for Dummies.pdf - Engineering Surveyor

Chapter 9: Interfacing a GPS Receiver to a Computer161onto a single, large-capacity memory card). This section talks about how toget the most out of your memory card GPS receiver. If your GPS receiver usesonly a cable to connect to a computer, you can skip this section. Better yet,read along to see how memory cards work for transferring data. (Figure 9-3shows a GPS receiver with a memory card.)If your GPS receiver supports using a memory card, you have some significantadvantages when exchanging data with a computer, including Upload speed: Uploading maps from your computer to a GPS receiver isconsiderably faster with a memory card than via a serial port cable.Because GPS receivers communicate at a fairly low baud rate, transferring10–20MB of map data can take a long time (up to hours dependingon how the serial port is configured). Affordable and practical: Memory cards have gotten inexpensive overthe years. You can load frequently used maps on several cards and notbother with repeatedly uploading data from map program CDs. You caneasily pick up a 128MB memory card, which I’d recommend as a minimumsize, for under $40. I like to use Froogle (http://froogle.google.com)to find the best prices online.Figure 9-3:A LowranceiFINDER andan MMCmemorycard.