F9P output NMEA to Case PRO600

We have been trying to send NMEA from a simplertk2b to a case pro600 monitor for yeild mapping purposes with meager success. Based off posts on agtalk i set the f9p to output GPGGA + GPVTG @ 38400N1 5hz. We are using a max3232 ttl-rs232 adapter board. As far as i can tell, tx2 on the f9p should be connected to tx on the max3232 (tx=max3232 DIN1 - Datasheet attached) and a null modem cable should be used to cinnect to the serial port on the pro600. After much trial, we have f9p rx2 connected to max3232 tx and connected to the pro600 with a straightthrough cable. As shown in attached pics, the pro600 switches between showing gps coords with a no dgps - (# of sats) error and showing nothing. I am confused by the uart pinouts as well as why the monitor is not happy with what i am sending it. It must be getting something since it shows coords periodically. The antenna is inside but i have 2/3d fix and position in u-center.
max3232.pdf (1.7 MB)






Today I got my f9p to output nmea to a topcon x20 monitor. Same converter as you have. I used tx2 on f9p and set UART 2 in ucenter to nmea out at 38400 baud rate. My biggest problem was it was set to gngga instead of gpgga. Once I read the right post on getting that changed it worked.

I am sending GP at the moment. Are you using a classic ardusimple f9p? Would you share your config? I must not have something right that it is sending from rx2

I believe that it is necessary to send in 1 hz the gga and vtg. On the other hand, you have to be careful to send in GP gga and GP vtg

I believe i have tried 1hz. Also tried 9600 baud. Definitely sending gpgga and gpvtg. Could it be the pro600 is looking for tsip? Or something special? Now that i think of it i may not have had 1hz with the correct config. Might try that. Any thoughts on why it only sends data from the f9p rx pin? Also why it only works without null modem cable.

No you don’t need 9600 precisely, the recommended configuration is what I sent you 38 400 and 1 htz. I have them working like this for 5 years with a novatel smart 6 antenna. And I have them working with an f9p this weekend for my brother, I will check the configuration for you when I can.

Yes you only need one wire, on the intelliview 3 it is connected to pins 10 behind the screen

Ok. Thanks. Will try again

I had found this file there is a lot of information
94036aa8-b0ca-46c5-b3d4-7c025b1b96f1E-07 - NMEA Out_Mapping with EZ-Guide_FM Displays .pdf (804,0 Ko)

Hello, I confirm that it works well, the setting and the following 38 400, GPgga, GPvtg and GPgsv in 1 htz.



Those are the settings i used! Can you provide more info about your wirings? Crossover cable/no crossover? What pins do you have connected on f9p amd max3232?

At least i know its possible! Thanks

I connected on top of the f9p on the xbe output because I don’t know why on the uart 2 its not working, maybe a bad configuration on my part. I would check but I think I connected the rx of the f9p to the tx of the max 3232 and then pin 2 and gnd of the rs232 to the harvester

Did you solve it? I want to use it on an AFS PRO700, and I’m also having trouble. But I used only a NULL MODEM. What changes if I use MAX3232?

This is right configuration for 600pro and 700pro

I need MAX3232?

yes yes you need a max 3232

Got it, because I was using all these correct parameters and with null modem. But it still wasn’t communicating. It must be the lack of max3232

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Correct. The Pro 700 requires RS232 serial, whereas the F9P outputs logic-level serial. That means 0v for a 0, 3.3v for a 1. RS232 is designed for longer distance (several metres), and for external use with cords and plugs, and uses much higher voltage levels for the signals. And in fact uses negative voltages for 0, positive for 1. The MAX3232 does bidirectional conversion between the logic-level signals and the higher-voltage RS232 signals.

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I have a micro F9P TX hooked to the max3232 TX. What pins should be connected on the rs232 side? Should the max3232 pin 3 be hooked to the pro600 pin 2 and pin 5 gnd to gnd?

I believe the Pro 700 RS232 port is male, correct? If so that’s the DTE version of the port, so it wants to receive on pin 2. So you’d want the MAX3232 TX output on pin 2 to connect to an RS232 female plug on pin 2 which will ultimately mate with the Pro700 which uses pin 2 as the RX pin.