Work is continuing slowly with the OpenGD77 and anyone using the Tier2 Alpha, should avoid using the Last Heard screen until I do another release.
I’ve updated the Tier 1 version, with a fix for this, as well as making some changes to the Tier1 version UI to unify the functionality with the Tier2 version.
This includes using Function + Star key to change from FM <–> DMR mode
Also a new feature that will be introduced in the next Tier2 Alpha 2, where during DMR Rx, if the transmit TG does not match the incoming Rx TG, the TG number is displayed in inverse video, (white text on a black background).
In the next Tier2 version, pressing Function when the TG is being shown in inverse video, will change the Tx TG to match the currently received TG.
Note. I don’t have time to put this function into the Tier1 version, as its a large duplication of effort and I am personally no longer using the Tier1 version unless I need to run the GD-77 as a hotspot.
I have also made some improvements to the ID display and most of the time the radio only shows the callsign or ID for stations on the selected TS.
Unfortunately, I have a number other serious problems with the Tier2 version which are currently preventing me from releasing a new version.
There seems to be a problem with the RAM getting overwritten by either part of the OpenGD77 firmware or possibly by the AMBE codec binaries. This problem seems to manifest its self on some people’s radios more than others, and not on my radio at all – which makes it very hard to track down.
Also, there seems to be a problem with the EEPROM access, so that sometimes the CPS can’t upload a new codeplug, and I suspect the codeplug data is sometimes getting corrupted when the settings are saved when radio is turned off.
There is also a bug where occasionally the radio transmits on the wrong timeslot.
And the Tier2 version seems to suffer from audio garbling more often than the Tier1 version. My guess at the moment is that this has something to do with CPU load and perhaps the CPU is not managing to decode the AMBE audio data quickly enough, especially if the BER is high or possibly if some audio frames are actually missing.
Memory bugs are notoriously difficult to track down, especially on a complicated piece of firmware like in the GD-77, likewise real-time bugs like the audio garbling are also hard to replicate and hence hard to bug fix.
So overall, I think its unlikely that I will be able to release a new Tier 2 version in the near future, unless some other developers come onto the project and can investigate the bugs in parallel with my work.
Whilst working on the Tier2 version, I noticed that the Last Heard screen was completely crashing the radio, and on further investigation I found a bug which also effected the Tier1 version.