A pattern generator is used to generate a user defined pattern of digital logic high/low signals or pulses. With theAnalog Discovery 2‘s 16 digital channels (32 channels for theElectronics Explorer Board), you have multiple options for generating whatever digital pattern you choose, from a single signal to a full 32-bit bus.
Defining the pattern on each channel couldn’t be simpler. There are a number of preset patterns you can use, like a Johnson counter or a constant value. You can also custom define each channel with a user-defined pattern.
You can also define a logic truth table and use the digital channels as the inputs or outputs for said table. Simply map the input/output pins using the property tab…
…and then define the truth table under the truth table tab.
For a more complete tutorial, check out myInstructable.
I have the EE Board and I’m having issues with Patterns. I’m trying to generate a digital pattern using 8 DIO lines (24 thru 31). I want each line to be PushPull, so that I get a steady alternating sequence of 0’s and 1’s on each line, at whatever frequency I wish to select for each line.
这是米y problem: Even when trying to set up one line, it seems that I’m not getting a stable, steady PushPull output like you’d expect for a clock signal. The output is shifting ‘back and forth’, as it were, as viewed on a scope (I’ve tried the Digilent virtual scope as well as another literal scope). It’s as if there’s a pattern to the shifting, as if the generator is outputting a good sequence of square waves, then resetting itself and outputting another sequence of good square waves. I need a steady sequence that doesn’t do any periodic shifting.
I’m not using any trigger inputs – rather just using it in free-running mode, as type Clock, output type PP.
Once I can solve this problem on the first line, I’d like to replicate it for the other 7 lines, except each one will be running at its own frequency. But, I’d also like to have all the lines sync’ed to line 1 as a clock line. Is this doable?
What am I doing wrong?
I would post this exact question at forum.blog.digilentinc.com and you should have a response from a moderator (or another concerned citizen) shortly!