Re: [gpsd-dev] SiRF gpsmon client mode

[Eric S. Raymond]

Gary E. Miller <address@hidden>:
> > > Yeah, I made it wider, but not wide enough for bad cases.  Also not
> > > sure why PPS is in the packet 7 box?  Clearly it is not in a packet.
> > 
> > Both problems have the same cause: we're badly short on screen space
> > if we want the top panel and at least one line of log window to fit
> > in a 80x25 terminal emulator.  I spent a lot of ingenuity packing
> > stuff in tight, but I admit the results are not entirely satisfactory.
> 
> Some programs, like atop, show more as the screen size grows.  Prolly
> a PITA to code, but a possible direction to go.  Or maybe some page
> flipping?

Possible.  SiRF mode already does something like this -- IIRC part
of the monitor panel changes according to a mode command.  But...

* If this is going to happen, post-3.12.

* I view gpsmon mainly as a way to smoke-test new hardware so people
  qualifying GPSes can check that they're alive and emitting sane data.
  I'm generally reluctant to add complexity to it, because it's not
  a production tool and thus the payoff relative to extra maintainance
  costs is not all that high.

I think making enough space for a full PPS offset *is* worth doing,
because that's a significant diagnostic for people setting up time
service.  But given a choice between dramatically increasing the
complexity of gpsmon and bumping something less important off the
screen, I lean in favor of the latter.

How many spaces do I need to give the PPS offset, worst-case?  I can
do a pass through the monitor implementations looking to see if I
can squeeze that in, though possibly not until after 3.12.

> > > Plus still the garbage on the right.
> > 
> > I think that garbage is remnants of what was onscreen before the panel
> > was painted.  You can test this by doing a 'clear' before calling
> > gpsmon; if I'm right, there will be no garbage.
> 
> Sort of.  I see the garbage is some JSON displayed after gpsmon
> starts and before the curses painted.  Annoying, but not fatal.

I just pushed a small patch that I think fixes this.  It does a clear
screen before each driver switch.

> > > Pull git head and check it out.  I think the PPS in gpsmon now 
> > > looking almost good.  Still need to fix that ntpshm_latch() is
> > > called more than once a second in gpsmon hardware mode.
> > 
> > It's on my list of things to look at.
> 
> I committed a small patch to fix that.  Better.  The PPS now looks good
> as I stare at it, so no obvious glitches in the steady state.

Yes, it's looking good here, too.
-- 
                <a href="http://www.catb.org/~esr/";>Eric S. Raymond</a>