Host Engineering Forum

General Category => Do-more CPUs and Do-more Designer Software => Topic started by: JeffS on July 22, 2020, 01:45:10 PM

Title: High Speed Timer - Dual Edge Timer
Post by: JeffS on July 22, 2020, 01:45:10 PM
So I have been messing around with the BX-DM1-18ER-D and using the dual edge timers.  From what I can see I can only have one active timer at a time, if two HS timers are enabled then they both accumulate if either is triggered.  This is a problem as I need to have two independent timers.  Am I doing something wrong, or can there only be one active HS timer?
Title: Re: High Speed Timer - Dual Edge Timer
Post by: BobO on July 22, 2020, 02:03:27 PM
Quote from: JeffS on July 22, 2020, 01:45:10 PM
So I have been messing around with the BX-DM1-18ER-D and using the dual edge timers.  From what I can see I can only have one active timer at a time, if two HS timers are enabled then they both accumulate if either is triggered.  This is a problem as I need to have two independent timers.  Am I doing something wrong, or can there only be one active HS timer?

You are probably driving them with the same input.
Title: Re: High Speed Timer - Dual Edge Timer
Post by: JeffS on July 23, 2020, 09:47:39 AM
Both use independent inputs.
Title: Re: High Speed Timer - Dual Edge Timer
Post by: BobO on July 23, 2020, 10:00:12 AM
Quote from: JeffS on July 23, 2020, 09:47:39 AM
Both use independent inputs.

That setup worked fine for me (my Xs and Ys are looped). Might be some crosstalk or noise on the inputs. Make sure your filter setting is appropriate.

Title: Re: High Speed Timer - Dual Edge Timer
Post by: JeffS on July 23, 2020, 12:48:39 PM
I had my filter set to 1us on these inputs.  Looking at the sensors I ended up moving it back to default of 10ms and that seems to work just fine.  Thanks for pointing me at the filters.
Title: Re: High Speed Timer - Dual Edge Timer
Post by: BobO on July 23, 2020, 01:30:59 PM
Quote from: JeffS on July 23, 2020, 12:48:39 PM
I had my filter set to 1us on these inputs.  Looking at the sensors I ended up moving it back to default of 10ms and that seems to work just fine.  Thanks for pointing me at the filters.

Fast = Sensitive. Just one of those engineering trade-offs.