I’ve now updated the OpenGD77 User Guide to include the new features in the Tier 2 Alpha 2 release.
A PDF of the guide can be downloaded from here
https://github.com/rogerclarkmelbourne/OpenGD77/raw/Tier2/docs/Open%20GD77%20User%20Guide.pdf
Notable changes to the functionality in the Tier 2 Alpha 2 version are as follow.
Signal meter on VFO and Channel screens
Inverse video display of received TalkGroup
If the Rx TG does not match the current Tx TG it is now displayed in inverse video to alert the operator that they will not be replying on the same TG.
Note. In the official firmware, the radio would transmit on the Rx TG if the PTT was pressed within a short time of the Rx signal ending, however this functionality is not ideal, as the operator may want to immediately transmit on another TG, For Example to force their hotspot to change TG.
So with the OpenGD77 firmware the operator can decide whether the want to transmit on the currently selected TG or…
If you wish to reply (Transmit) on the same TG as the received signal. Press the Function / blue button on the side of the radio while the TG is being displayed in inverse video and the Tx TG will be changed to match the Rx TG.
Channel and VFO quick menus
The Orange button functionality has been changed to provide a context senstive menu on both the Channel and VFO screens. Currently there are only a few functions available, but I will add new functions at a later date.
Channel mode quick menu
The Channel mode quick menu only currently has one option. This will copy the current channel to the VFO.
Press the Green button to copy or the Red button to cancel.
VFO Quick menu
The VFO quick menu currently has 3 options.
These copy or exchange the Tx or Rx frequencies
Note. To listen on the input of a DMR repeater, both the Tx and Rx frequencies need to be set to the Rx frequency of the repeater (the Tx frequency of the radio). This is because of the underlying Tier 2 Active or Passive mode selection, is hidden from the operator, and selected by the firmware depending on whether the Tx and Rx frequencies are the same
If Tx freq = Rx freq then the radio will be in DMR Active mode, otherwise the radio will be put into DMR Passive mode.
In DMR passive mode, the radio assumes its listening to a repeater which transmits both TimeSlots and the repeater is the synchronisation master, where as in Tier 2 Active mode the radio is the DMR master on Tx and operates to receive the single Timeslot pulses sent by another DMR radio.