Digital Waveform Example

[jeffdillon]

I need to read 8 digital lines, and plot their state continuously over time, like a strip chart. I've seen the Digital Waveform examples that come with LabView 6.0, but they appear to only take a snapshot in time. The state on each line may change every second, for example. Any examples available? I'm using a NI 6024E.

[Rob Cole]

I see 2 possible solutions to this (off the top of my head anyway):

1) the digital waveform graph uses an array input, so store all of your inputs in an array and feed that array to the digital waveform graph. As new data comes in, shift the new data into the "top end" of the array and the old data off of the other end.

2) Use the waveform chart indicator. The waveform chart default is to automatically scale the Y axis. If the input you have is boolean, convert it to 0's and 1's using the Functions/Numeric/Conversions/Boolean to (0,1). If you have voltages, you can define your "1" voltage (eg. 5 volts) to read as 1 on the Y scale (turn off the automatic scale on the Y axis).

I would prefer to use option 2. Especially if you have a lot of digital lines to watch
.