Are you seriously saying that you haven't done this already
Thanks, we have done it, and the DALI pulses at the micro's DALI RX pin looks perfectly normal.
As you know, what we cannot scope, is in the myriad of bus's and circuitry within the micro itself.
Microchip write app notes to show how their MCUs can be integrated into products that maufacturers have the field-specfic expertise to design , i.e. "Hey DALI people, you can use a PIC in your design - here's a starting point", not "Hey lighting manufacturer, here's everything you need to know to create a DALI interface.
Thanks, attached to this post is one pulse of the DALI signal that we are receiving...and this is what it looks like when the DALI comms is **not** working...as you can see, its a very amenable pulse
.......and its produced by the circuit on page 3 of AN1465......we can think of no earthly reason why a softy couldnt write code to correctly receive that pulse in....even despite its obvioulsy fairly slow rise time.
I know FA about DALI except is is the industrial equivalent of DMX, but looking at diagrams 'ground loop' comes into my head. What happens if the laptop runs on batteries?
Thanks, I see what you mean, -because the laptop, the DALI PSU, and the lamp itself all have connections to earth, and these can all “see each other”…and even the secondary of the DALI PSU will be able to “see” earth …(ie through the Y capacitors which must exist inside it)……..however, if a “Badboy” earth loop is causing our problem, then you’d think the problem could be solved by disconnecting the earth from the lamp and then it would work…..but, this is not the case, and , in fact, disconnecting the lamp’s earth connection is one thing that makes its DALI receive not work.
I suppose we can console ourselves that in the real installation, there will not be a laptop installed up with the product.
I must admit I am in some small way surprised that none of the other contractors in our company that we have spoken to about our problem have said that our lack of any AC mains filter in our lamp could be causing the problem………I mean, surely since the problem is most likely caused by the laptop drawing noisy pulses from the lamp’s input (due to the high mains impedance looking back to the mains), then I would have thought a filter at the AC input to our lamp would be the obvious solution?
…and at that, a common mode filter instead of a diff mode filter.
Also, getting the softy to receive the DALI pulses by consecutive 50us reads and then reconstructing the DALI pulse train, seems like a good idea….but again, the other contractors here have just brushed it aside.