With Icom rigs that use MAIN?SUB VFOs there is a trade off when
setting the mode or frequency of the "other" VFO. Untill now Hamlib
uses the XCHG VFO command to address the "other" VFO. This has some
advantages, particularly it preserves the selected VFO and it
preserves memory mode of either VFO. The disadvantage is that any
split command causes the Rx to glitch when the VFO/MEMs are exchanged.
I have added a config parameter for Icom rigs called "no_xchg" which
forces the direct addressing of VFOs to set split mode/frequency. It
is a boolean option with a default of "0" (false) which equates to
prior behaviour. Setting it to "1" (true) will make the backend use
change VFO commands to set the "other" VFO. This means that TX on
"SUB" in split is assumed, that both are in VFO mode (not MEM), and
set/get split functions will leave the MAIN VFO selected.
Michael Black