Re: Low cost GPS receiver?

[Chris Kuethe]

I haven't used a serial device in a long time that actually required EIA232 signaling. Everything I've used in the last decade was 5v or 3v. Definitely not to spec, but works far more often than it has any right to. Burning up the pin drivers on a chip that isn't 5v tolerant is another matter, but that's what the datasheet is for. Most devices I use clearly document their absolute maximums: 3.6v for a 3.3v device, or 5.5v if there's likely to be usb nearby (+10%). 

If you genuinely do need real EIA232 levels the MAX232 and similar parts have built in charge pumps to generate the required voltages. I'm betting that a pc with a 5v level shifter with work just fine with a GPS. 

On Wed, Mar 29, 2023, 23:31 Sanjeev Gupta <ghane0@gmail.com> wrote:

Chris, one side of the level shifter is 3.3V, the other is 15V.  If I am powering it by the VCC at 3.3 or 5V, how does this work? 

There is obviously a simple answer, but I cannot formulate the Google query.

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Sanjeev Gupta
+65 98551208     http://www.linkedin.com/in/ghane

On Thu, 30 Mar 2023 at 12:35, Chris Kuethe <chris.kuethe@gmail.com> wrote:

Pretty much any of the GPS receivers we mentioned would work on a raspberry pi plugged in with dupont jumpers.

You can get level shifters with DB9 connectors for about the same price as a GPS module.

https://www.amazon.com/NulSom-Inc-Ultra-Compact-Converter/dp/B00OPU2QJ4/

This one even has pins and dupont jumpers

https://www.amazon.com/DaFuRui-Converter-Connector-Equipment-Upgrades/dp/B07Z5Y1WKX/

And then you power the gps receiver over usb but ignore the native ublox serial port.

On Wed, Mar 29, 2023 at 9:14 PM Sanjeev Gupta <ghane0@gmail.com> wrote:

Gary, once an year, I ask for this, often on this list.

The "problem" I see with most modules like these is the UART voltage.  (Nearly) all are designed for Aurdino, so they work on 3.3V (TTL?) logic.  I think HAL would like to plug this into an RS-232 port in a "server", so he needs the +12/-12V signals.

I don't see those products under $200 :-(

--
Sanjeev Gupta
+65 98551208     http://www.linkedin.com/in/ghane

On Thu, 30 Mar 2023 at 07:08, Gary E. Miller <gem@rellim.com> wrote:

Yo Hal!

On Wed, 29 Mar 2023 15:07:07 -0700
Hal Murray <halmurray@sonic.net> wrote:

> Is there a popular low cost GPS receiver that requires (at most) only
> moderate amounts of soldering?

Ebay has many under $10:

https://www.ebay.com/itm/275756616309

https://www.ebay.com/itm/373651892261

https://www.ebay.com/itm/174653466203

Try to avoid anything older than u-blox 8.





RGDS
GARY
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Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
        gem@rellim.com  Tel:+1 541 382 8588

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GDB has a 'break' feature; why doesn't it have 'fix' too?