How to export rtk NMEA0183 from teensy to rs232

You need to connect rx, tx and gnd.

i want to do the same thing on an AIO micro board, which pins do i connect for that on the f9p. ?

Hey @Arek84 are you using dual gps or single gps?

I am using single and connected to tx1 on f9p and did the setup for uart 1 in ucenter so my setup was like this
Uart 1 output nmea
Baud rate 38400
Nmea messages 10 hz for gga, vtg, and rmc
My monitor gets the messages and everything as expected but my ag open tablet loses gps and dont have rtk on the monitor.

What i noticed was when i submitted 38400 on uart 1 then teensy light quit blinking .

What could i try. ? I guess i could do same as yours on uart2 and do setup at 57600 baud rate…

Hello @customfordfan im going to 2020 seedsense as well.
Do you mind sharing which pinout you used on the f9p and what numbers you used in setup?

I assume you’re using an All in one board, since you talk about a teensy. Somebody more knowledgeable can correct me, but I believe you need to leave UART 1 alone, as the teensy communicates with the F9P over UART1 at a baud rate of 460,800. If you have a AIO micro board with single, you can export your nmea from UART2 on one of the two pins highlighted in white.

This post, might give you some ideas.

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Precision planting says to use 5 Hz. for the 20/20, but I used 10 Hz at 38400 baud all spring with no issues.

You must use uart2, uart1 is reserved for teensy.

I got it working .
Thanks for the help

Hou you guys put the signal out? Do you use ttl to233 module in cable? Or like me glue it to exbee headers and use lert over pins like 14 or 13 to send it to the 23 ampseal?

For mine i mounted the converter right in the face plate of the plastic box wher 2 nd antenna would mount and tgen i can install serial cable on outside anytime for connection.

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Looks great. Do you have .stl for the cover with rs233 opening?

Im trying to learn all this stuff and its kinda working but as for the cover .stl i do not.

Actually i just used the original cover and a fine tip paint marker and a little die grinder and drill bit and 10 min later there was a hole there!

Thnx for the info.

This is how i do now. But will make new pcb layout with ttl to 232. I have 2 next to eachother now 1 for nmea and 1 for xte output

Something like this

hello, would it be possible to have more photos of the fixing of the RS232 module? Notably do it. did you just drill and put back the original screws? does this leave enough room for the DB9 socket?

Hello. Yes i msde a hole for the plug first and die grinder around till the plug fit through. It had to be a bit over sized so that when you go to attach your plug on the outside that the thin metal layer has room to slide in between the bix cover plate and the newly installed serial socket. Then i drilled the two holes for the screws last and yes i used the original screws they are long enough to go through the plate and still have full hold in the thread in the back piece.

Hey guys . Im stumped with how to get nmea output working with dual gps. If i set it up the same way as single then left receiver never gets rtk . Im pulling the signal on uart 2 on right receiver

On dual, the right sends data to the left on uart2. Uart1 on both talk to the Teensy so you could probably send nnea out of the left uart2 but it has to be at the same baud as the right is sending the left.

Also the problem with dual GPS is your nmea will only be coming from one of the receivers, so it will be offset if your antennas are equally spread out left and right from the center line.