OpenGD77

so No possibility for open gd 77 ?, I bought it specifically for this, to install open gd 77, holding down the two low keys under ptt does not enter download mode Windows Do Not Recognize the programming cable , the cable is the same for baofeng uv5r

yes IT9HMB

hi, sorry for my english but i'm using translate and i'm sorry if i opened a new discission but i didn't find anything about my problem:
my 1801A just arrived, but trying to put in firmware mode nothing happens, someone who can help me to install open gd77 on my dm1801A?