OpenGD77

Some info on that radio with the Auctus chip, which may be of interest to GD77 users: the battery looks as it could be compatible, it actually fits in and can power the GD77, but does not lock. The contact plate is a tiny bit too thick for the battery to fit in the GD77 all the way. Other info, whic...

So I'm not sure how you are going to talk to anyone else unless its via simplex I understand the "chicken and egg" problem, but projects need to start somewhere. For example, I am building a mcHF transceiver right now, because it natively supports freeDV/codec2 (on its arm processor). I don't expec...

VK3KYY wrote: ↑

Mon May 17, 2021 9:27 pm

The binary sections contain all sorts of code and data, not just the codec, but its all mixed together like its been in a blender.

OK. Then the answer to the question is "very difficult to do". Thank you.

Thank you for the answer.

I thought that the original firmware used quite a bit of memory space for the Chinese language. Is that still in the openGD77 version? If yes, maybe some space could be freed?

Use the source, Luke! ;) Obviously, all questions asked on any forum can be answered by "read the fine manual". But I would expect that someone who has actually worked with the firmware code base could answer that particular question relatively easily: "would it be doable to replace the binary blob...

ve7mdt wrote: ↑

Mon May 17, 2021 3:12 am

Is the expired one for the original AMBE or the AMBE+2 ? I am not sure if there is just 1 version?

The expired patent is for the AMBE codec, the one used in the D-Star protocol. The patents for the AMBE+2 are still valid, but will lapse eventually.

In answer to do1jml. There is no special hardware for the codec. It is run on the arm processor by the binary blobs. (we assume this is licenced code from DVSI but we have no way of confirming this). Thank you for the info. Is the interface to the "binary blob" documented in the code? How difficult...

I'm afraid that it's not possible, because the algorithm is patented, and you can't reimplement it neither by HW or by SW means unless you have an agreement with the patent owner. First, the original patent for the ambe codec (US6199037) is expired and, second, the DMR standard does not mandate the...

Sorry to come to that subject again. Am I right in my understanding that the present GD-77 firmware includes a binary blob from the manufacturer and that this blob corresponds to the voice codec (ambe2+)? That means that the code to compress and decompress audio data runs on the MK22FN512 ARM proces...

I can hear some OM's but quite often,the green LED comes on, indicating some activity but I can't hear anything. I tried monitor mode (promiscous mode) on as well but that doesn't change anything. There may be non-voice activity on the repeater. A check on the local repeaters with a SDR shows them ...