I want to make a GPS car locator using a GPS and a cellphone with inbuilt modem. I would make a data call to the cellphone and it would relay the GPS data to me.
The GPS sends data via serial, and the phone accepts data via serial. I cannot connect the two directly together for two reasons;
- the deluge of GPS data confuses the modem when it is not in a connected state
- If there is no GPS signal at the time I call, I'm out of luck.
I want to make a logic device with two serial ports (one for GPS, one for phone) and a data buffer. It would listen in on the GPS port and parse out the co-ordinates from the data. If the co-ordinates are present (has GPS signal) then it would store those co-orindates in the data buffer. If the co-oridnates are not present (No GPS signal) then it woudl ignore the data (and the data buffer still contains the last good co-ordinates).
It would also listen to the cellmodem port. If it sees the word "CONNECTED" come across the line then it would start relaying the data from the data buffer. If it sees the word; "NO CARRIER" it would stop relaying.
All the basic stamps I have seen so far only have one serial port.
- Is this a reasonable project to attempt with a basic stamp?
- How do I get two serial ports with a single basic stamp?
- Can I hook up an RS232 chip to some of the data lines on the stamp and use that as my second serial port?
- Is there an alternative to using a basic stamp? It would be mounted in a car and run 24x7, so a computer is not an option.
Thanks!
The GPS sends data via serial, and the phone accepts data via serial. I cannot connect the two directly together for two reasons;
- the deluge of GPS data confuses the modem when it is not in a connected state
- If there is no GPS signal at the time I call, I'm out of luck.
I want to make a logic device with two serial ports (one for GPS, one for phone) and a data buffer. It would listen in on the GPS port and parse out the co-ordinates from the data. If the co-ordinates are present (has GPS signal) then it would store those co-orindates in the data buffer. If the co-oridnates are not present (No GPS signal) then it woudl ignore the data (and the data buffer still contains the last good co-ordinates).
It would also listen to the cellmodem port. If it sees the word "CONNECTED" come across the line then it would start relaying the data from the data buffer. If it sees the word; "NO CARRIER" it would stop relaying.
All the basic stamps I have seen so far only have one serial port.
- Is this a reasonable project to attempt with a basic stamp?
- How do I get two serial ports with a single basic stamp?
- Can I hook up an RS232 chip to some of the data lines on the stamp and use that as my second serial port?
- Is there an alternative to using a basic stamp? It would be mounted in a car and run 24x7, so a computer is not an option.
Thanks!