On Wed, Dec 23, 2009 at 1:28 AM, firdaus adinugroho <[email protected]> wrote:
> I have two sensors need to be installed beside the GPS. The output > of the sensor is an analog one with voltage 0-5V. I expected to get > GPS data and also those sensors data. Okay, you're in luck! 0-5V is exactly what you'll want! > Based on the information that the T2-301 has two Serial Port, can > I connecting the GPS trough Serial Port 1, and converting the > sensors to RS-232 output, then connect them to Serial Port 2 ? That's a lot of work that doesn't need to happen. The OT2 line has the ability to send telemetry data, which should allow you to do what you want. If you provide your sensor voltage to the appropriate pins on the tracker2, you can have the unit send the sensor data at specified time intervals. As Keith already pointed out, http://wiki.argentdata.com/index.php/Telemetry has a fairly good run down on the telemetry capabilities of the OT2. (I wonder who wrote that page???) The OT2 has one spare telemetry input available that can accept 0-5V input. You can hang one of your sensors off that input without much fuss. Adding the second sensor means that you either lose one of the default sensors, or you'll need to rewrite the code used by the OT2. The easier option is to pull something, like the voltage divider, and inject your sensor data where the voltage divider input used to be. If you configure the tracker to send your telemetry data, you will get a packet sent that looks something like this: 2009-12-23 09:27:06 MST: EDSON>APOT21,EVNBRG*,WIDE2-1,qAR,VA6KRM-10:T#216,139,179,250,000,000,00000010 The data from the onboard sensors are encoded in the values 139 and 179. If you want to use that information in an external application, then you will need a program that will pull the value out of the packet which you will need to pull from the APRS data stream. If you just want to be able to manually monitor the values, then making use of something like the aprs.fi server is great. http://aprs.fi/telemetry/EDSON?range=month At this site, I am only watching the battery voltage, and the internal shack temperature. The other telemetry values are null. Hope that helps. James VE6SRV
