Multiple data sources

[Bob Watzlavick]

I want to add an additional data source to our CDS. The primary data
source would be from an L-3 550 console but we want to bring in an
additional source of data directly to the CDS from our weather
station. The data will actually come over a serial port to a machine
in the TM room (possibly the CDS) but I'm assuming I can use a socket
interface from any machine. I was looking at the example
(iadsDataSource.zip) up on the website but it doesn't appear obvious
how to specify a second datasource in the startup file. I saw a post
from early 2007 that said this was an upcoming feature - is it
supported yet?

Thanks,
-Bob

[Jim Bretz]

Bob,

Yep... But:

1) I think the CDS only supports a "Custom" secondary data source, and not a
secondary Tpp etc. Sounds like you're going "custom" here, so no worries.

2) A little word of "caution" about time alignment. The CDS is going to use
the "master" data source's current time value to stamp the secondary
source's data. If absolute perfect time alignment isn't an issue, then we're
good to go here. Sounds like from the type of data involved, it's not going
to be a problem if data doesn't align to the main stream in the millisecond
range. We're working on improving this issue.

Ok, now for the answer. Basically, you just add some additional entries to
the CDS init file (or Ops startup file but you need to change the format of
course):

All you do is create "_2" or "_N" entries describing the data path:

DATALOCATION = CDSName 49000
DATALOCATION_2 = WeatherStationPC 49002
DATA_SOURCE_BUFFER_SIZE_IN_MILLISECONDS = 20
DATA_SOURCE_BUFFER_SIZE_IN_MILLISECONDS_2 = 20
DATA_SOURCE_TYPE = OS90
DATA_SOURCE_TYPE_2 = Custom
DATA_SOURCE_PROGID = IadsOS90DataSource.IadsOS90DataSource.1
DATA_SOURCE_PROGID_2 = IadsCustomDataSource.IadsCustomDataSource.1

Of course, you're setting for the 550 are different, but I think you'll
understand the pattern. I'm pretty sure the setting are limited to the "Data
Source Section" of the init.

Make sure DATA_SOURCE_TYPE_2 = Custom and DATA_SOURCE_PROGID_2 =
IadsCustomDataSource.IadsCustomDataSource.1, launch the CDS and the data
source and see what goes. I'm thinking you can setup the data source exe in
the OpsConsole so it starts automatically.

Hope this helps... Sorry for not being 100% sure on these answers. I'm
stretching the limit of my knowledge here (i.e. reading the code as I type).
Mike might chime in soon to correct me..
Jim

[Watzlavick, Robert L]

Perfect - the secret decoder ring for the init file is just what I
needed. We'll give it a try. Thanks! BTW you're right about the
timing. Using the master source's timestamp should be sufficient for
weather data.

Is this supported in 5.3.2 or is it only in 6.0?

-Bob

[Jim Bretz]

Bob,

> Perfect - the secret decoder ring for the init file is just what I
> needed. We'll give it a try. Thanks! BTW you're right about the
> timing. Using the master source's timestamp should be sufficient for
> weather data.

;) You're in the club now...

> Is this supported in 5.3.2 or is it only in 6.0?

Yep.... It's in 5.3.2, but you didn't have the secret ring so you couldn't
see it,
Jim

[Mike Burt]

There are a couple more entries that apply to multiple data sources:

MODE = SIMTPP
MODE_2 = SIMTPP

PARAMDEF = ./parameterDefinitionFiles
PARAMDEF_2 = ./parameterDefinitionFiles/iadsCDS.prn