Question About eTrex GPS and BS2
I just bought an eTrex GPS unit and a connecting serial cable. What is the best way to connect my BS2 to this unit? Specifically, what pins from the GPS's serial cable go to power, ground and the BS2? I read an article in NV about a project involving a car speedo and the eTrex -- so I know it can be done. But I am confused about the physical connections. Thanks!
Comments
www.parallax.com/dl/docs/cols/nv/vol3/col/nv83.pdf
I haven't read through the whole article again, but that diagram and the relevant text seems to show the eTrex cable/connector simply has a ground (black) and a data (white) conenction. The white lead is data which seems to simply goto an input pin on the BS. Looking at the top of the program list halfway down the article, the code declares one pin for the data input, and reads data straight away in main: using SERIN
Do you not just connect the white lead to a pin on the BS2p, and ground the other lead? That seems to be all that's required.
What have you tried so far?
Perhaps there is a workaround to this, Jon or Chris should be able to help if so...
Standard DB9 RS232 wiring
If you want ALL the gorey details, try this: www.garmin.com/specs/pcwiring.pdf
Post Edited (pwssr) : 4/25/2006 6:42:38 PM GMT
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Jon Williams
Applications Engineer, Parallax
pin5 on the db9 goes to ground!
help! it's not working
i am trying to do something like this:
if alt > 1000 then: LIGHTON
if alt < 300 then LIGHTOFF
but it doesn't treat alt like a number?
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OS-X: because making Unix user-friendly was easier than debugging Windows
I don't see what program you're using, but I suspect I may see the problem. The variable "ALT" MUST be defined as a WORD, if its to have values greater then 255 in it. A byte can only contain values from 0 ==> 255.
If "ALT" is an input variable (from a SERIN) then it must be read in as alt.highbyte and alt.lowbyte, as asynchronous serial data is transmitted on a BYTE basis, and it take 2 BYTES to make a WORD.
Regards,
Bruce Bates
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OS-X: because making Unix user-friendly was easier than debugging Windows