Hooking up a GPS to a Nano

Hi, new member here!

Im working on a project where i will be using a GPS with a Arduino Nano and I was lucky enough to get some free samples of a GPS called ORG1411 PM04 (http://www.origingps.com/products/org-1411/)

And i have some questions regarding how to hook it up to the Nano. Normally you would connect the power to the Vcc then Rx to Rx and so on, but after reading the datasheet (http://www.origingps.com/wp-content/uploads/2014/11/Nano-Hornet-ORG1411-Datasheet2.pdf) im a bit confused since this is somewhat new to me (the areas of concern in the data sheet are from point 17 to 18).

So here are my questions.

  1. Can I power the GPS with arduino pins since the output 5 volts?

  2. What does this mean? "TX used for GPS data reports. Output logic high voltage level is LVCMOS 1.8V compatible."

  3. Does this mean I have to put a resistor between the Nano and the GPS to go from 5v to 1.4v-3.6v? "RX used for receiver control. Input logic high voltage level is 1.45V, tolerable up to 3.6V."

  4. What pins do I actually need to use (see data sheet 17.1)?

Any answers are appreciated!

It won't work with a Nano. You need a 1.8V to 5V logic level translator.

aarg:
It won't work with a Nano. You need a 1.8V to 5V logic level translator.

If I were to add a logic lvl converter (example: https://www.sparkfun.com/products/12009) would it work then?

digestivekex:
If I were to add a logic lvl converter (example: https://www.sparkfun.com/products/12009) would it work then?

Yes.

aarg:
Yes.

Great!

Have i understood this right?
Pin +5v -> HV1 -> LV1 -> Vcc
Pin GND -> GND -> GND -> GND
Pin TX -> HV1 -> LV1 -> TX (GPS)
Pin RX -> HV1 -> LV1 -> RX (GPS)
Pin X -> HV1 -> LV1 -> ON_OFF (GPS)
Pin Y -> HV1 -> LV1 -> WAKEUP (GPS)

Looks good, except that you should be aware that you are using the hardware serial pins of the Nano. Those are already in use by the USB interface (which gives you serial I/O and allows you to use the bootloader). You can do it, but you have to give up the USB serial connection to do it. The usual solution is to connect using SoftwareSerial on some other pins.

Also, I think (please check) that you would apply 5V directly to the module Vcc, as it has an on board regulator. I don't see where WAKEUP appears on the external connections. Which module do you have, and which connector are you connecting to? Just the module, or the demo board?

aarg:
Looks good, except that you should be aware that you are using the hardware serial pins of the Nano. Those are already in use by the USB interface (which gives you serial I/O and allows you to use the bootloader). You can do it, but you have to give up the USB serial connection to do it. The usual solution is to connect using SoftwareSerial on some other pins.

Does that pose any kind of problem for me, or does it just mean that i have extra "functionality" in those pins?
If I were to swap to I2C or SPI, would i need anything else or would i be fine using this translator?

First, let's be absolutely sure we're talking about the same part. SMT module? EVK? Or?

aarg:
First, let's be absolutely sure we're talking about the same part. SMT module? EVK? Or?

Im not talking about any SMT module or EVK. Im talking about connecting a GPS (this one: http://www.origingps.com/wp-content/uploads/2014/11/Nano-Hornet-ORG1411-Datasheet2.pdf ) which can use the interfaces UART SPI and I2C for communication. To achive this i would use a Level shifter/Logic level translator to bring down the 5v from the arduino to ~3.3v so I dont fry the GPS.

Are we on the same level so far?

Well, not really. That is an SMT part. If you look at “18. TYPICAL APPLICATION CIRCUIT” you will see what is required. Note that it calls for an LDO regulator. 3.3V would fry the module, as the absolute maximum supply voltage is 2.2V.

aarg:
Well, not really. That is an SMT part. If you look at "18. TYPICAL APPLICATION CIRCUIT" you will see what is required. Note that it calls for an LDO regulator. 3.3V would fry the module, as the absolute maximum supply voltage is 2.2V.

Are you sure? I have the version that is shown in "figure 11" where it says Vcc 2.2V - 5.5V. I thought that meant that the supply voltage can be between 2.2 and 5.5V?

PS whats a LDO?

digestivekex:
Are you sure? I have the version that is shown in "figure 11" where it says Vcc 2.2V - 5.5V. I thought that meant that the supply voltage can be between 2.2 and 5.5V?

PS whats a LDO?

Well, I followed the link you gave me, so if it's different, it's on your end. http://www.origingps.com/wp-content/uploads/2014/11/Nano-Hornet-ORG1411-Datasheet2.pdf

Do you have the PM-01 or the PM-04 ordering option? Be sure.

How are you planning on mounting the module? Was software provided, or do you have to write your own?

aarg:
Well, I followed the link you gave me, so if it's different, it's on your end. http://www.origingps.com/wp-content/uploads/2014/11/Nano-Hornet-ORG1411-Datasheet2.pdf

Do you have the PM-01 or the PM-04 ordering option?

Did not mean to come of in an offensive way in my last post, if I did, im sorry.

I have the PM04.

Great. So all you need now is a Murata NFA31GD1004704. :slight_smile: I sort of kid, sort of not. This type of module really requires a careful integration into some PCB design. You might be able to make it work, with slightly compromised performance. Look further down at the suggestions for PCB implementation. It’s not really supposed to be a hobby level design job. That’s why the integrated modules are so popular. It’s also why the company offers the design kit PCB. They have all that work done for you.

You haven’t commented on how you plan to mount it. Software might not be a big issue, as it has NMEA output on both serial and I2C.

aarg:
Great. So all you need now is a Murata NFA31GD1004704. :slight_smile: I sort of kid, sort of not. This type of module really requires a careful integration into some PCB design. You might be able to make it work, with slightly compromised performance. Look further down at the suggestions for PCB implementation. It's not really supposed to be a hobby level design job. That's why the integrated modules are so popular. It's also why the company offers the design kit PCB. They have all that work done for you.

You haven't commented on how you plan to mount it. Software might not be a big issue, as it has NMEA output on both serial and I2C.

What is Murata NFA31GD1004704? All i find is a catalog page.

Yeah i know i have to mout it on a PCB and that is the plan. But right now i want to test things out before going off finding someone who can design and produce a board for me.

Would the previous setup mentioned (nano plus level shifter that supports i2c plus gps) work just to see some results?

The Murata is an RF noise decoupling device. If you follow the reference design you can probably make a test version work, under perfect conditions. You may be able to get away without the filter, just for testing out the computer interface. It would not be wise to leave it out of the final design.

aarg:
The Murata is an RF noise decoupling device. If you follow the reference design you can probably make a test version work, under perfect conditions. You may be able to get away without the filter, just for testing out the computer interface. It would not be wise to leave it out of the final design.

Does get rid of noise in the signal?
Okay, just to make sure ive understood this correctly.

I could right now use the nano with gps + level shifter to see some results but when/if i decide to make PCB for the gps i should also include a RF noise decoupling device?

digestivekex:
Does get rid of noise in the signal?
Okay, just to make sure ive understood this correctly.

I could right now use the nano with gps + level shifter to see some results but when/if i decide to make PCB for the gps i should also include a RF noise decoupling device?

Yes. You should spend a while reading and fully understanding the manufacturers implementation recommendations in parts 18-20. Take them seriously.

aarg:
Yes. You should spend a while reading and fully understanding the manufacturers implementation recommendations in parts 18-20. Take them seriously.

Great! This is stuff is really new for me so I have alot to wrap my head around but I'll make sure I have a good understanding of everything before putting it on a PCB. Im also quite sure I'll be back here with more questions. Thanks for the help :slight_smile:

Typical Vcc for the ORG1411 PM04 is 3.3V… Why not get an Arduino that also uses 3.3V logic levels, so you can run the whole thing of a LiPo battery? Powering 5V devices with batteries is a pain. And you don’t need to worry about logic levels exceeding some voltage either.