In order to have a better idea how the device is working. I recommend setting one port as an output and another one as input, and connect the output port to the input.
The following discussion forum might be of interest to you as well.
Hooking the inputs from Port 0 to the outputs from Port 1 works, but what I'm trying to do is like on the older 6508 is have the channels come up in a high state (5 volts) when the unit is powered up and then ground the channels to change the state (0 volts). But when the channel is removed from the ground the state stays at 0 volts instead of returning to 5 volts like I think it should.
Does this not work on the 6509 like it did on the 6508?
If the "Test Panels" is NOT running and the board is reset (or just powered up) I can ground the channels and they will return to 5 volts when the ground is removed. When the software is running it will not do this.
Does the 6509 use internal pull-up/pull-down resistors on the digital I/O lines? Do we have to add our own pull-up resistor to each line?
I'm using a volt meter to read the voltages off the channels.
OK so the 6509 doesn't work exactly like the 6508. We'll have to add pull-up resistors to each channel.
Thanks for your help...
Hi - Ran into the same issue on the 6509, but unable to understand why is Test Panel behaving different? Is it not the Test Panel where the initial state(s), whether tri-state/low/high, constitute initial states of the I/O?
It looks like this thread has been inactive for a few years. You may want to consider creating a new question to get some discussion from the community.