How to Setup GPS Module and Use it as a Geolocator?

[ame]

is it possible that the solder or J2 is upside down? so maybe its lower to center or upper to center?

No, J2 is not upside down. And certainly the solder should be "lower to center or upper to center". The artwork shows the pads, and also shows the silk-screen artwork indicating '1' for pin 1 of the three pads of J2. Also, if you look at the artwork you can see the centre pad (pad 2) connects to R1, the lower pad (pad 1) connects to the 5V supply, and the upper pad (pad 3) connects to the output of the 3.3V regulator. So, you want a solder blob connecting 2 to 3 (upper to centre).

[peter145]

Ok, sorry, the PCB artwork on page 4 is very clear. The solder pads are very close together in an oval pattern with *two* horizontal splits, which makes three segments to the right of R1. The top one is pad 3, the middle is 2, and the bottom one is 1. Can you see which two segments are joined with a solder blob?

If it's 1-2 (lower to centre) then you need to remove the solder, then re-apply solder to pads 2-3 (upper to centre).

If it's already 2-3 (upper to centre) then you're good to go.

so its currently connected to "Lower Center 1-2" Vlogic - 5volts.....

so i have to desolder it and connect it to "Upper centre 2-3" Vlogic - VDD

here is a picture and the link for bigger size picture for reference:
http://imageshack.com/a/img853/5450/kb5s.png

[ame]

Yup. It should take a very short time to melt the solder blob and make a new one across 2-3. After doing this, inspect the pads carefully and make sure there is nothing between 1 and 2.

How are your soldering skills these days?

[peter145]

Yup. It should take a very short time to melt the solder blob and make a new one across 2-3. After doing this, inspect the pads carefully and make sure there is nothing between 1 and 2.

How are your soldering skills these days?

I'm very good at drilling small holes on a pcb but soldering really is not my forte thats why i stay away from it

so VDD is the regulator connection? Can you point out in the board where my 3.3v regulator is?

[ame]

I'm very good at drilling small holes on a pcb but soldering really is not my forte thats why i stay away from it

so VDD is the regulator connection? Can you point out in the board where my 3.3v regulator is?

Ok, well, it's a tiny solder job so as long as you know which is the hot end I think you'll be able to manage it.

According to the schematic on page 3, the 3.3V regulator is component U1 (it is a 1117-3.3 regulator).

From the silkscreen layout on page 4 we can see U1 is marked at the lower left of the PCB, just above the reset switch.

If you look at a data sheet for a 1117-3.3 you can see that one of the three pins is the output, but also the large tab on the other side of the package is connected to the output. If you follow the trace from the tab you will see that it goes up, and through pin 1 of JP5, then to the right and touches components C5 and C2 then R2. Then it touches C3 (and U2) and goes through the PCB to the other side. You can see on the artwork for the bottom layer that the trace goes a short way down the back of the PCB and through the board again. Then it connects to pad 3 of J2.

[peter145]

I'm very good at drilling small holes on a pcb but soldering really is not my forte thats why i stay away from it

so VDD is the regulator connection? Can you point out in the board where my 3.3v regulator is?

Ok, well, it's a tiny solder job so as long as you know which is the hot end I think you'll be able to manage it.

According to the schematic on page 3, the 3.3V regulator is component U1 (it is a 1117-3.3 regulator).

From the silkscreen layout on page 4 we can see U1 is marked at the lower left of the PCB, just above the reset switch.

If you look at a data sheet for a 1117-3.3 you can see that one of the three pins is the output, but also the large tab on the other side of the package is connected to the output. If you follow the trace from the tab you will see that it goes up, and through pin 1 of JP5, then to the right and touches components C5 and C2 then R2. Then it touches C3 (and U2) and goes through the PCB to the other side. You can see on the artwork for the bottom layer that the trace goes a short way down the back of the PCB and through the board again. Then it connects to pad 3 of J2.

What If I use the 3.3 volts power output of the raspberry pi in powering my gps module?

would it make a difference?

would it solve the problem of serial interfacing?

Whats the use of the Uncommited pins og JP5?

[ame]

What If I use the 3.3 volts power output of the raspberry pi in powering my gps module?

would it make a difference?

would it solve the problem of serial interfacing?

Whats the use of the Uncommited pins og JP5?

That... is a very good question.

According to the schematic, 5V (on JP1) is connected only to the regulator and J2. This means that all of the circuit, including the GPS module itself, is powered from 3.3V.

If you connected 3.3V output from the Pi to the 3.3V pin on JP1 then you would indeed be supplying all of the components after the regulator with 3.3V.

However, I foresee the following problems:
1) You will be feeding 3.3V into the *output* of the regulator. I don't know what the regulator will do. It might be safe, or it might consume current.
2) You will be drawing current from the Pi's on-board 3.3V regulator. I don't know how much current the GPS board uses, and I don't know how much the Pi's regulator can provide (remember, it's already powering the Pi). It's possible that the GPS would draw too much more current.
3) The pullup resistor R1 is still connected to Vlogic, which is still connected to 5V, which (in this scenario) is connected to... nothing! So you probably won't get data out of the GPS.


Regarding JP5, it looks like it's just a convenient connector to access all of the other signals that do not appear on any of the other pins. This allows you to easily plug in your own circuits, or to monitor or control some of the less-commonly used features of the GPS module. The egizmo company made the PCB which allows you to easily use the GPS module, but they did not design the GPS module itself. You can find out all about the GPS module by reading its datasheet here:

http://file01.up71.com/file/corpdownfil ... 145920.pdf

[peter145]

What If I use the 3.3 volts power output of the raspberry pi in powering my gps module?

would it make a difference?

would it solve the problem of serial interfacing?

Whats the use of the Uncommited pins og JP5?

That... is a very good question.

According to the schematic, 5V (on JP1) is connected only to the regulator and J2. This means that all of the circuit, including the GPS module itself, is powered from 3.3V.

If you connected 3.3V output from the Pi to the 3.3V pin on JP1 then you would indeed be supplying all of the components after the regulator with 3.3V.

However, I foresee the following problems:
1) You will be feeding 3.3V into the *output* of the regulator. I don't know what the regulator will do. It might be safe, or it might consume current.
2) You will be drawing current from the Pi's on-board 3.3V regulator. I don't know how much current the GPS board uses, and I don't know how much the Pi's regulator can provide (remember, it's already powering the Pi). It's possible that the GPS would draw too much more current.
3) The pullup resistor R1 is still connected to Vlogic, which is still connected to 5V, which (in this scenario) is connected to... nothing! So you probably won't get data out of the GPS.


Regarding JP5, it looks like it's just a convenient connector to access all of the other signals that do not appear on any of the other pins. This allows you to easily plug in your own circuits, or to monitor or control some of the less-commonly used features of the GPS module. The egizmo company made the PCB which allows you to easily use the GPS module, but they did not design the GPS module itself. You can find out all about the GPS module by reading its datasheet here:

http://file01.up71.com/file/corpdownfil ... 145920.pdf

Im gonna start soldering tomorrow so... what will be the next step?

[ame]

Ok, well, take your time. It's a tiny soldering job, but take care.

Next step is to attach four wires from the Pi to the GPS module. Make sure the power is off, then attach 5V, GND, Tx and Rx as described already. Hopefully you have some jumper leads with sockets on one end, like these ones:
https://www.sparkfun.com/products/9385

Or you can hack something together.

Then you need to prevent the console from using the serial port:
http://elinux.org/RPi_Serial_Connection ... erial_port

Then you should be able to use minicom or something to see the GPS data coming in to /dev/ttyAMA0

Are you in the Philippines, by the way?

[peter145]

Ok, well, take your time. It's a tiny soldering job, but take care.

Next step is to attach four wires from the Pi to the GPS module. Make sure the power is off, then attach 5V, GND, Tx and Rx as described already. Hopefully you have some jumper leads with sockets on one end, like these ones:
https://www.sparkfun.com/products/9385

Or you can hack something together.

Then you need to prevent the console from using the serial port:
http://elinux.org/RPi_Serial_Connection ... erial_port

Then you should be able to use minicom or something to see the GPS data coming in to /dev/ttyAMA0

Are you in the Philippines, by the way?

Yes im in the Philippines

By the way I found this link(https://github.com/lurch/rpi-serial-console) piece of resources that makes Controlling the Serial much easy... What' your recommendation about the link i gave you?

[peter145]

I just read the skylab manual at it said

UART Ports:
The module supports two full duplexserial channels UART0 and UART1. All serialconnections are at 3V CMOS logic levels, if need different voltage levels, use appropriate level shifters.The baud rate of both serial ports are fully programmable, the data format is however fixed: X, N, 8, 1, i.e. X baud rate, no parity, eight data bits and one stop bit, no otherdata formats are supported, LSB is sent first.

Does that mean that my logic levels are already 3volts?

[ame]

I just read the skylab manual at it said

UART Ports:
The module supports two full duplexserial channels UART0 and UART1. All serialconnections are at 3V CMOS logic levels, if need different voltage levels, use appropriate level shifters.The baud rate of both serial ports are fully programmable, the data format is however fixed: X, N, 8, 1, i.e. X baud rate, no parity, eight data bits and one stop bit, no otherdata formats are supported, LSB is sent first.

Does that mean that my logic levels are already 3volts?

Well, it might do. Sorry to be so vague, but I don't have the same hardware and I don't want to give you bad advice. But indeed that's what the manual says.

You can access the unbuffered signals from the UART conveniently on JP5 as TXD0 and RXD0. I can foresee two issues. The first is that you now have to 'cross over' the signals, since TXD0 is an output, and hasn't been swapped over by the wiring of S2 (so you have to connect it to Rx on the Pi).

The second issue is if you connected the Pi Tx line to the module RXD0 line that you now have two signals 'fighting' on the RXD0 pin. You will have the signal from the Pi and the output of the buffer chip U2. I don't think this is a Good Thing, but it can be avoided (see below).

Personally, I would resolder J2 to give me a 3.3V interface, but it's your money and your risk. If you want to try without doing that, and without the buffers then here's what I'd do. Note that GPS modules usually only send stuff *out* and there is rarely any need to send anything *to* the GPS. So, you only need three lines:

1) 5V from the Pi to 5V on the module
2) GND (0V) on the Pi to GND on the module
3) TXD0 output on the module (JP5) to Rx input on the Pi

That's it. If TXD0 really is 3.3V then it's safe for the Pi GPIO. And the fact that TXD0 is connected to the input of a buffer transistor won't matter.

Try it and see. If you damage something then I'm sorry. You'll have to buy a new Pi or a new GPS module, but that's the price of learning. I think it'll work though.

[paulie]

If anyone wants a pre-wired cable to interface Adafruit's Ultimate GPS,
I use a spare audio lead from a PC CDROM. Vin, GND, NC(RxD not used), TxD.
As long as you don't need to send data to the device, and you connect to the right pins,
it just works.

[ame]

If anyone wants a pre-wired cable to interface Adafruit's Ultimate GPS,
I use a spare audio lead from a PC CDROM. Vin, GND, NC(RxD not used), TxD.
As long as you don't need to send data to the device, and you connect to the right pins,
it just works.

This module is not the same as Adafruit's Ultimate GPS. But I agree, CDROM audio cables are handy 4-pin wiring harnesses.

[peter145]

If anyone wants a pre-wired cable to interface Adafruit's Ultimate GPS,
I use a spare audio lead from a PC CDROM. Vin, GND, NC(RxD not used), TxD.
As long as you don't need to send data to the device, and you connect to the right pins,
it just works.

This module is not the same as Adafruit's Ultimate GPS. But I agree, CDROM audio cables are handy 4-pin wiring harnesses.

well i just did the soldering way so next is to connect what pins to the Raspberry pi?

By the way I found this link(https://github.com/lurch/rpi-serial-console) piece of resources that makes Controlling the Serial much easy... What' your recommendation about the link i gave you? Should i Enable or diable my serial console?

I just soldered the jumper 2-3 for 3.3logic level (which is connected now to my VDD not directly to 5volts)so :
1.Connect +5v Raspberry pi (what pin?) to +5volts to Gps module
2. Connect the jp4 Tx to Tx(What pin?) of raspberry pi? and jp4 Rx to Rx on raspberry PI(What pin?)?

[ame]

If anyone wants a pre-wired cable to interface Adafruit's Ultimate GPS,
I use a spare audio lead from a PC CDROM. Vin, GND, NC(RxD not used), TxD.
As long as you don't need to send data to the device, and you connect to the right pins,
it just works.

This module is not the same as Adafruit's Ultimate GPS. But I agree, CDROM audio cables are handy 4-pin wiring harnesses.

well i just did the soldering way so next is to connect what pins to the Raspberry pi?

By the way I found this link(https://github.com/lurch/rpi-serial-console) piece of resources that makes Controlling the Serial much easy... What' your recommendation about the link i gave you? Should i Enable or diable my serial console?

I just soldered the jumper 2-3 for 3.3logic level (which is connected now to my VDD not directly to 5volts)so :
1.Connect +5v Raspberry pi (what pin?) to +5volts to Gps module
2. Connect the jp4 Tx to Tx(What pin?) of raspberry pi? and jp4 Rx to Rx on raspberry PI(What pin?)?

Good job on the soldering. I think it's the best way, and now you have some knowledge and experience.

Now, pins.

You forgot to mention GND. It is important.

Also, I don't think you need the Tx signal for data from the Pi to the module. So that means only 3 wires are necessary.

Take a good look at the diagram here:
http://elinux.org/RPi_Low-level_peripherals

Make sure you know which is pin 1, and how the pin ordering works from 1 to 26. Next, when you are connecting to these pins be careful not to let your wires touch the pin next to it. Finally, double-check the pin number.

1) 5V supply
Take 5V from the RPi to power the module. You can use pin 2 on the GPIO header, or pin 4. Connect it to the module 5V pin on JP1 (pin 3).
2) GND
You must connect GND from the Pi to the module. You could use any GND pin on the GPIO header, but maybe pin 6, as it is next to pin 4 (+5V). Connect it to one of the GND pins on the module (e.g. JP1 pin 4)
3) GPS data
This is the data transmitted from the GPS to the Pi. Connect RX on the module JP4 to RXD on the Pi (it's pin 10).

That should work, but for completeness you could connect TX on the module JP4 to TXD on the Pi (it's pin 8) if you want to.

You may have noticed that these 4 pins are together on one edge of the GPIO connector. If you ignore the first 5V pin (pin 2) then the rest are next to each other in this order: +5V GND TXD RXD (pins 4,6,8 & 10).

Double check the orientation of the GPIO connector. If you count from the wrong end then you will get the wrong pins and damage something.

Finally, the script you linked to might be useful. You can do the work by hand if you like, but the script is easier I suppose. You need to 'disable' the console because you are using the serial port for your own purpose.

[ame]

well i just did the soldering way so next is to connect what pins to the Raspberry pi?

Just double checking. You soldered 2-3. Did you remove the solder from 1-2?

[peter145]

well i just did the soldering way so next is to connect what pins to the Raspberry pi?

Just double checking. You soldered 2-3. Did you remove the solder from 1-2?

yes i soldered top-center and desoldered bottom-center... it was kinda hard cause they painted the soldered piece with varnish...and the solder blob is so small...

By the way you know any php scripts and LXE codes for connecting it to your Raspberry pi to a domain name through php?

Can I use the ada code for sending the GPS data through GPSD?

[ame]

yes i soldered top-center and desoldered bottom-center... it was kinda hard cause they painted the soldered piece with varnish...and the solder blob is so small...

By the way you know any php scripts and LXE codes for connecting it to your Raspberry pi to a domain name through php?

Can I use the ada code for sending the GPS data through GPSD?

I'm not sure I understand the question.

Are you receiving data from the GPS now?

[peter145]

I'm not sure I understand the question.

Are you receiving data from the GPS now?

Here is the things i did:
1. I installed the gpsd and used $sudo gpsd /dev/ttyAMA0 -F /var/run/gpsd.sock
2. Then I type cgps -s to show wether my gps is sending data through the pi
3. I waited for like 30 minutes and it says NO FIX status
4. But i noticed when i Exited my the cgps it says "cgps caught 2 signals" what does it mean?

What should I do?

[ame]

Here is the things i did:
1. I installed the gpsd and used $sudo gpsd /dev/ttyAMA0 -F /var/run/gpsd.sock
2. Then I type cgps -s to show wether my gps is sending data through the pi
3. I waited for like 30 minutes and it says NO FIX status
4. But i noticed when i Exited my the cgps it says "cgps caught 2 signals" what does it mean?

What should I do?

I think you should ignore gpsd for now and verify that there is something coming in from the GPS on the serial port.

Try installing minicom and opening the /dev/ttyAMA0 port

http://www.raspberry-projects.com/pi/pr ... g-the-uart

You can follow the instructions "Using minicom on the UART". The -b parameter should match the baud rate of the GPS module. I can't remember the default, but it ought to be in the module datasheet.

On the minicom screen you should see some data coming in once per second. If it's garbled, try a different baud rate. If you see nothing then you need to figure out why.

[peter145]

Here is the things i did:
1. I installed the gpsd and used $sudo gpsd /dev/ttyAMA0 -F /var/run/gpsd.sock
2. Then I type cgps -s to show wether my gps is sending data through the pi
3. I waited for like 30 minutes and it says NO FIX status
4. But i noticed when i Exited my the cgps it says "cgps caught 2 signals" what does it mean?

What should I do?

I think you should ignore gpsd for now and verify that there is something coming in from the GPS on the serial port.

Try installing minicom and opening the /dev/ttyAMA0 port

http://www.raspberry-projects.com/pi/pr ... g-the-uart

You can follow the instructions "Using minicom on the UART". The -b parameter should match the baud rate of the GPS module. I can't remember the default, but it ought to be in the module datasheet.

On the minicom screen you should see some data coming in once per second. If it's garbled, try a different baud rate. If you see nothing then you need to figure out why.

The gps Modules baud rate is 9600

[ame]

Ok, so you want

minicom -b 9600 -o -D /dev/ttyAMA0

[peter145]

Ok, so you want

minicom -b 9600 -o -D /dev/ttyAMA0

Here is what I did(I attached photos for reference):
1. I used the 115200 rate instead of 9600 :

http://imageshack.us/photo/my-images/69/bj3x.jpg/


2. Used "gpsd -n" Command here are the results:



http://imageshack.us/photo/my-images/811/hwfw.jpg/
3.I used "cgps" command and the STATUS: NO Fix (For about 10 or more minutes):



I really think the number one problem of my gps is the SIGNALING maybe i need to go out and get the antenna to have a sky VIEW to have a fix signal. when I turn off the CGPS it says "CAUGHT SIGNALS 2"

http://img31.imageshack.us/img31/9421/jvl4.jpg

[ame]

That's fantastic!

The first photo tells you everything you need to know. It shows you the following things:

1) The module has power
2) The module is running
3) You have successfully wired the serial data lines
4) You have successfully taken control of the serial port
5) You have the correct baud rate

The most important thing is the line that starts $GPRMC. The third field is "V" which means there is no satellite fix. It's working perfectly!

Do the same thing (ignore gpsd for now) and put the GPS module near a window. The GPS signal is too weak to work well indoors. If you can get a signal through the window then when you watch the screen eventually you will see latitude and longitude results. The third field of the $GPRMC sentence will change to "A" which means there is enough satellite information for a valid lat/lon fix.

When that is working, try gpsd.