Postcard firmware update and assembly

GPS/GNSS
1

I’m receiving my RTK Postcard and Portability Shield in a few hours. I’m new to Sparkfun products and might have missed some published documentation. I am really looking forward to using the Postcard!

Question 1:
How do I update all relevant firmware for these devices and the Quectel LG290P? It seems like I need to update the Quectel LG290P using QGNSS and the firmware from this Github issue comment? In addition I need to update the RTK Everywhere firmware? The Postcard product page links to a Github repository, but the Github repository doesn’t list the Postcard as a supported product. Are there any firmware updates for the Portability Shield? I find this all really confusing. Could you please give me a list of required files and a step-by-step guide? I bet other users would also benefit from updates to the guides and the Github repositories.

Question 2:
When will the hardware assembly / hookup guide be completed? (I’m apparently only allowed two links per post, but here’s the guide: docs DOT sparkfun DOT com/SparkFun_Portability_Shield/hardware_assembly/). Right now the guide for connecting the Postcard to the Portability Shield consists of a single photo showing only one side of the Postcard and Shield soldered together. Some text and additional photos or drawings would make this much easier for less experienced users. Maybe also include which direction each board should be facing when soldered together.

I appreciate any help you can give. Thanks!

2

Welcome to the Forum @mag :slight_smile:

I don’t work for SparkFun, but I’m glad to share a few of my notes from upgrading the PostCard’s Firmware.

Download and install QGNSS, per the GitHub issue you linked to.
While this is mentioned in the Guide, you will also need to have a Serial Terminal connected to the port that includes “Serial A” in the description to Reset the LG290P within 20 seconds of uploading FW in QGNSS.

Here’s my notes:
Updating LG290P -
Use QGNSS V2, select the com port that mentions Serial B in the description, Baud rate is 460800
Also have a serial terminal connected to the port that mentions Serial A in it’s description, Baud rate is 115200 - this is how you reset the LG290P within 20 seconds of Flashing with QGNSS. Go ahead and navigate to the Debug Hardware menu in your serial terminal of choice and be ready to send command 13 after you flash with QGNSS.

Clip from the Git you linked to:

image
image778×887 69.4 KB

To update the PostCard’s RTK Everywhere firmware is very straighforward.
Use the RTK Uploader Tool, select the port that mentions Serial A in it’s description, Baud rate is 115200. Download the latest .bin from here, which is currently RTK_Everywhere_Firmware_RC-Jan_20_2025.bin as of today, and flash it.

Note, the PostCard will work right out of the box (and without the Shield). It just wont send GST messages until you update the FW. I decided not to use my Portability Shield, so I didn’t solder the headers. I’ll let someone else help you on that one :wink:

Summary:
To monkey with LG290P => Serial B, baud rate 460800 (this will be rare)
To monkey with the PostCard => Serial A, baud rate 115200 (update PostCard FW)

The PostCard is a brand new Product. I’m sure the documentation will catch up soon to add the LG290P FW flashing procedure, and the Shield install.

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3

Hey @mag,

On the Postcard product page, the last image in the carousel shows a full board assembly: SparkFun RTK Postcard

The header pin hole alignment is asymmetrical, so as long as you don’t solder one of the boards on upside-down, and you make sure that every pin hole has a header pin, it should be self-aligning. The silkscreened pin identifiers should be aligned between the boards (5v pin to 5v pin, GND to GND, etc…).

The boards are meant to be stacked with the smooth side facing inwards (which allows space for a small battery to rest there), and the screen should be oriented so that the SMA connector is just behind it.

As for when the docs will be done; that is a work in progress. If I had to guess, I’d say within the next 2-3 weeks; but we have a lot of exciting stuff coming down the pipeline for PNT, and that has slowed down our normal process a bit. Our apologies for that, we just got a little too productive for our own good, and now we are playing catchup!

Please let me know if you need more details on the assembly; I fully understand the “I want to be sure before I heat up the soldering iron” point of view.

Cheers

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4

After you get it all assembled be sure to enable GST messages. and then go over to GNSS LG290P latest FW - #18 by george.gao - GNSS Module - Quectel Forums and request more decimals in GST messages. Maybe if enough of us say it it will happen faster. (I can’t imagine it takes much work to increase reporting decimals in the FW)

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5

We also host the Quectel firmware versions here. I see we’re missing the firmware update docs for the Postcard. I’ll get that corrected shortly.

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6

I got everything up and running with your help. Thanks a lot, guys!

I’ll add a few notes to what’s already said:

  1. The RTK Everywhere firmware from this Github repository also works for the Postcard, even though the repository only lists the Torch and EVK as the supported hardware.

  2. I would recommend updating the RTK Everywhere firmware before the LG290P, since this commit from the 13th of January adds the menu item to reset the LG290P.

  3. I had to enable the GST message twice in the serial menu after the update. If you follow the guide above and still don’t have accuracy information in SW Maps, go back to the serial menu and verify that the GST messages have actually been enabled.

  4. Soldering the boards together is easy if you follow @swells advice to stack them with the smooth side facing inwards. I used a male header to solder both together, leaving a 2mm gap between the boards (the black header plastic is 2mm, which is what I used to space them appart).

  5. I was struggling to find the accepted voltage range for the LiPo battery on the Portability Shield. Digging through the component list I found the AP2112K which has a recommended supply voltage between 2.5V and 6.0V. I don’t know if that also applies to the Portability Shield, maybe someone else knows? A standard 3.7V LiPo battery seems to work fine though.

I’m still quite unsure how the Portability Shield works. There’s a lot of weird text and icons on the screen that I haven’t been able to understand. The menu is also very limited: practically all you can do is switch between base and rover mode, and activate the WiFi AP. The SD card only logs NMEA and not Rinex, and the only documentation on how to change that is for u-blox devices.

The firmware folder for the Portability Shield only contain example code, so I don’t really know how I can improve it myself. Link: github DOT com/sparkfun/SparkFun_Portability_Shield/tree/main/Firmware

I’ll contact Quectel to ask about AGNSS estimates. I already have access to Quectel AGNSS data from a previous GNSS chip, but it’s apparently not supported on the LG290P. If anyone else knows something about AGNSS on the LG290P I would love to hear it.

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7

Hi mag - I truly appreciate you coming back and giving us an update. This is our fault - the docs haven’t been updated. We’re struggling to get the RTK Everywhere product manual docs updated for the Postcard, and with your feedback, we’ll get it even better.

Thank you!

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8

Mag,

Thanks for the feedback! Always helpful to hear the good and the bad of user experience, helps us figure out what to focus on.

1> We’ll get it added to the list.

3> Interesting… I don’t believe I had to do that for mine, but now I want to make sure

4> Thanks! I did the same for my narrow stack housing design, which I put one of our large 1s3p batteries into for very long battery life! We’ll have that housing on the repo soon as well.

5> 3.7v is the only battery voltage I would recommend because it is all I’ve tested, though with the specks on the charger IC, perhaps others would work? I’ve had good results with these two:

  • There’s a lot of weird text and icons on the screen that I haven’t been able to understand.*

We are still working on our detailed manual for the Postcard specifically. Much of the iconography is taken from here, though it has been modified for the larger screen size.

  • The menu is also very limited: practically all you can do is switch between base and rover mode, and activate the WiFi AP*

We tend to keep the menu’s pretty simple, being able to see information about accuracy and Satellites in View, and swapping around modes. For any in-depth settings changes, a phone or computer is going to be a much better interface than the 5-way joystick.

  • The SD card only logs NMEA and not Rinex*

So, if the Postcard is in Base mode, it will log RTCM; RTKLib knows how to turn RTCM into RINEX. I’ve done many successful PPP runs using just the Postcard with stock settings in Base mode.

The Mosaic-x5 is the only unit we sell that has on-device conversion to RINEX, but it is also a much more expensive device with a high complexity. Our idea with the Postcard was to keep things simpler, cheaper, and configurable.

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