Custom device: how to plan for dynamic number of channels

[scofield]

Hi,

I'm planning to start developing a custom device, that will log the data in TSV format. Now the problem I'm experiencing is, I don't know how to go about dynamic number of channels. What I mean by dynamic number of channels is, the user should use this custom device to log the VeriStand channels:

1. Number of VeriStand channels will be different for different VeriStand projects (dynamic number of channels).

2. How to link the channels with the Custom device.

Please help.

[timtamslam]

Hey scofield, 

1. The number of channels that exist and are handled by the VeriStand engine, depends on how many you add to your custom device in the System Explorer. The number of available channels you have in the System Definition file depends on how many channels you create for the Custom Device in the Initialization VI. I would recommend looking at the Planning Custom Device section (page 17) of the VeriStand Custom Device Developers Guide. It expands a bit more on the Initialization VI and how it modifies the channels under your custom device in the System Explorer. 

2. Can you expand on what you mean here? Are you talking about linking the channels in the custom device between the gateway/engine while the system is running, or linking within the System Eplorer?

[Jarrod_S.]

The Embedded Data Logger custom device, which now ships with VeriStand, used to only be downloadable from our add-ons website. An older version of it is still available there and contains source code that you could use as an example. It likely has many of the same requirements that you have, except that it logs TDMS instead of CSV. You might check it out.

http://zone.ni.com/devzone/cda/epd/p/id/6240