clarification on Baofeng DM-1701 and GPS

[vk6hax]

Hi,

The documentation here https://github.com/LibreDMR/OpenGD77_Us ... ide.md#gps suggests that the Baofeng DM-1701 has GPS. However I've not been able to find a GPS enabled variant for sale anywhere and a fellow ham who has a Baofeng DM-1701 has told me that it is not GPS enabled.

Could someone provide further detail? Is this a documentation issue or is there a GPS enabled version of the radio somewhere? Or a way to install a GPS module?

[VK3KYY]

I think this is a paste'o in the User Guide.

The normal DM-1701 does not contain a GPS

The UV380 comes in either GPS or Non-GPS versions, as does the MD-9600, but I'm not aware of a version of the 1701 with GPS.

The User Guide needs to be ammened to show that the GPS options are only available for radios which have a GPS fitted, as not all MD-9600 or UV380 etc contain GPS.

[PU4TCR]

how can i activate my gps in Baofeng 1701 with opengd77 ?

[VK3KYY]

how can i activate my gps in Baofeng 1701 with opengd77 ?

There is no GPS in the DM1701

If you want to connect a GPS module to the MCU chip

NMEA serial data input pin is PA 10
Power enable is PA 9

Note.

The power enable pin is not able to supply the full current of a GPS module, you need to build a circuit of a PNP and NPN transistor to control the power to the GPS module from the power enable signal.

I have opened my DM1701 and there is very little room inside and it would be difficult to fit a GPS module and antenna inside this radio, however you could fit a GPS module outside the radio.

[PU4TCR]

how can i activate my gps in Baofeng 1701 with opengd77 ?

There is no GPS in the DM1701

If you want to connect a GPS module to the MCU chip

NMEA serial data input pin is PA 10
Power enable is PA 9

Note.

The power enable pin is not able to supply the full current of a GPS module, you need to build a circuit of a PNP and NPN transistor to control the power to the GPS module from the power enable signal.

I have opened my DM1701 and there is very little room inside and it would be difficult to fit a GPS module and antenna inside this radio, however you could fit a GPS module outside the radio.

Perfect VK3KYY ! Tks my friend!

[ve2wkr]

Yes, I did this and it did not work.
Fitting the antenna is not a problem, just get an 8mmx8mm antenna and fit it between the top knobs.
The GPS module goes behind the knobs.,
However attaching to PA10 killed the USB port to connect to the PC.
So I can no longer load the radio. I am not sure why , but I guess that USART is used for the USB com port.
73's
Luca

[VK3KYY]

Yes, I did this and it did not work.
Fitting the antenna is not a problem, just get an 8mmx8mm antenna and fit it between the top knobs.
The GPS module goes behind the knobs.,
However attaching to PA10 killed the USB port to connect to the PC.
So I can no longer load the radio. I am not sure why , but I guess that USART is used for the USB com port.
73's
Luca

You probably shorted some pins

USB is on PA11 and PA12

Check you did not short PA11 to PA10 or even short PA11 and PA12 etc together

[SQ9KCU]

Hello.
Is it possible to direct the GPS pin to one of the pins of the USB port? Switch USB / GPS in the DM1701 menu?
It would be easy to use an external GPS receiver by connecting it with a modified USB-C cable.
The power supply for the GPS receiver can be external.
Vy 73
SQ9KCU

[VK3KYY]

Hello.
Is it possible to direct the GPS pin to one of the pins of the USB port? Switch USB / GPS in the DM1701 menu?
It would be easy to use an external GPS receiver by connecting it with a modified USB-C cable.
The power supply for the GPS receiver can be external.
Vy 73
SQ9KCU

No.

I checked the data sheet for the STM32F405 and neither of the USB pins PA11 and PA12 can be configured as UART Rx.

And just in case anyone asks about the GD77. The same applies. The USB pins on the MCU can not be used as UART, in fact on the MK22FN512 MCU used in the GD77 the USB pins can only function as USB, they can't be reconfigured even as GPIO

[SA0BUX]

Just a thought I had regarding the GPS function.

How does the software "know" that a GPS is available ?

On my radios (RT3S,DM-1701) without GPS, I can't even enable it.