(GNC255) Blank the last digit when in NAV mode

[tigert]

Currently the last digit on NAV mode is not cleared in NAV mode, as NAV frequencies are NNN.NN and not NNN.NNN like COM frequencies with 8.33kHz spacing, and you need to pad the NAV frequency value before sending it to the display, or the old last digit of the COM frequency will be left on the screen when you switch to NAV mode.

Adding a trailing space with padding does not seem to work, maybe the value gets converted to a number at some point and the last space is being lost.

[elral]

Adding a trailing space with padding does not seem to work, maybe the value gets converted to a number at some point and the last space is being lost.

That's known from the connector, I run into the same issue when working on the KAV FCU display. See also:

• Transform modifier loses format '0.0' and uses '0' instead. · Issue #1628 · MobiFlight/MobiFlight-Connector (github.com)

Workaround could be $ + '   o', means add a non digit character after the spaces (here 'o') and send it to the board. The spaces gets ingnored when converting the string to a value and the non-digit character marks the end like a terminitaing NULL.

/edit: Oh wait, I have to double check the code

[tigert]

This seems to do it.

• First Round() to NNN.NN,
• Then pad to 6 characters, in case you have like 117.10 which becomes "117.1" because MF drops trailing zeros.
• Then pad it to NNN.NNN to wipe out the last digit of the COM frequency, if we just switched to NAV.

MSFS2020 is weird. Like that 117.10 is not really 117.100 but 117.09999999, go figure why? :-) But the Round() takes care of that too.