OpenGD77

Hey,
I just recived a tyt md 760 and first tried my baofeng programing cable which worked on the new version of the dr1801uv. The Open GD 77 CPS however cant detect the device when I try to flash the new firmware. Than I tried soder a direct usb cable following a schema I found online. Now I see a unknown device poping up in the Windows device manager. So I guess its a driver problem but when I try installing the driver from the archived open gd 77 repo, it will get stuck at the installing the drivers stage. I got it to unpack the files and than apperently sucessfully install the usb_device.inf file from the right click dialog. I tried on 3 computers already all running Win 10 Pro and Home. Also one of the pcs was 32 bit but I had no sucsess on either of thoose mashines. Do I need the tyt programing court or what am I doing wrong? Sorry for bothering, but I tried for 8h by now.
Thanks in advance vy 73 DK7ON

There are two standards of programming cable for different manufacturers. I think TYT and beofeng are different . They are identical except the D+ and D- signal lines are swapped.
The ground remains the same. +5V is not needed.

If you have made your own cable try swapping the D+ and D- lines.

Colin.

Hi, thanks for the reply. I dont think that you quiet got what i already have done. I don't think its a cable problem why would windows than recognize the USB cable its clearly a driver issue. The driver install however doesn't work.
Cheers Konrad

As Colin said,
a MD-760 IS a GD-77, only the sticker is different. Hence, it needs a "GD-77" cable (wiring).
All Baofeng cables (RD-5R, DM-1801) ARE different, D+ and D- are reversed.

If you ask for help, at least give people some credits about their knowledge...


Cheers.
---
Daniel

Sorry, my bad I was more referring to my text above that I missed out on important details. However I have now three cables that I tried using for programing one baofeng cable which I have tried switching tx and rx, then I tested a standard USB to serial chip also in both directions and now I found a schema for the gd 77 in the internet which is directly soldered to a USB a port and I tried that one. It gets recognized in windows as a unknown device so I guess it has something to do with the drivers, but I can't manage to install them via the stock cps from radiodittity nor the installer I found in the github archive. I tested with two machines both running latest version of windows 10 and both arm64.
Sorry for my bad explanation to begin with. 73 Konrad

OK.

So. The official firmware acts as a USB HID device. It does not require a driver for eithe firmware upload or the CPS codeplug data comms.

The OpenGD77 uses the official bootloader, hence uses the same USB HID driver that is part of Windows.

After the OpenGD77 firmware installed and is running the firmware acts as a USB Com device (USB CDCACM). This is the only time that a driver is necessary.

So if you can't install the firmware its not a driver problem, because neither the offcial firmware or the OpenGD77 install a driver for firmware installation.

If Windows shows Unrecognised device when the official firmware is running or the radio is in firmware update mode (bootloader) then perhaps the radio is faulty, if you are certain the problem is not your cable.

Because for both of these condions there is no special driver.

Hi, thank you for your help. It worked now with resodering the connections, so you were spot on with your prediction. Thanks for all the work and help you put into that project and sorry for my bad English. Have a nice weekend. 73 Konrad.