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Any update on this? ATM I can't use the board to control things because the output never changes.
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because now during china holidays, we will check when we begin to work.
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It's been nearly a month and I still can't use the board to control an output device, has there been any progress on this?
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these days will update new firmware.
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I think I've found the problem, it's caused by the way the output circuitry is set up. The output LED for e.g. DO1 is lit when there's a voltage between Y1 and GND, whether the output is on or not. In other words instead of being before the output MOSFET, which would only cause it to be lit when the TLP181 optocoupler output is on, it's after the MOSFET, so if Y1 is connected to something with a pullup then the output LED will be lit even with the MOSFET switched off.
I'll need to do some rewiring tomorrow to test this, I'll post the results here.
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I've confirmed that this is in fact the problem, the external device (which is a black box, I can't see the insides) has a pullup or something similar on it which puts a small voltage across the output pin. This means that the output LED is lit even when the output is off.
Is there any reason why the output-on LED is set up to indicate the presence of a voltage on the output pin rather than being between the optocoupler and the MOSFET, so actually indicate whether the output is on? Putting it before rather than after the MOSFET switch would avoid issues like this.
