Re: [9fans] it's live

[Ronald G Minnich <rminnich@lanl.gov>]

Anthony Sorace wrote:
> i know you said "more later", but i'm impatient.
>
> i *think* this is really cool, but i'm not entirely sure. that is, i'm
> sure there are cool bits, but i don't know which ones. how's the thing
> work? i assume the embedded system's connected directly to the GPS, as
> you talked about a while ago, but isn't the web server. how's that
> transfer happen? and what system/web server is doing the overlay?

The board is a lippert cool frontrunner. Kernel is on IDE-FLASH, soon to
be on DOC. GPS is a fortuna U2, serial port, 9600 baud. Modem is from
airlink, and provides PPP.

SO, board boots p9, runs a /rc/bin/cpurc that starts up ppp over the
modem (I stopped using telco -- it kept dying on me); mounts from
mbgokhale.org; mounts my hacked gpsfs; and, once a minute, does this:
cat /mnt/gps/gps.xml >> /whatever-i-called-it/dsn/gps.xml

That's it. easy as pie. Well, not that easy, there were a LOT of
practical issues, but the node at this point is very reliable. And, I
would not have wanted to do this with Unix.

mbgokhale.org runs an httpd with a bit of code josiah england wrote to
integrate the gps data into google maps. Again, easy in principle, a lot
of work in practice. But it works.

There's a lot more to it, but I need to write it up. But, let it suffice
to say that Plan 9 sure makes this type of thing easy.

thanks

ron