XMC1300 VADC : Understanding Queue Request Source

Hi all,

I am starting to work with the XMC1300 family of Infineon.

I have some troubles to understand how the Queue Request Source of the VADC works according to point 2.4, page 14 of the Application Note AP32304.

1) First, in this page, we can the following figure (Figure 8 in the document):

Attachment 2296

Could you please explain exactly how do we get from Ta to Tb?

If we have a FIFO, and the sequence is CH1, CH1(with trigger), CH5,CH3, and CH0 (with trigger), where CH0 is the first channel to be converter (First Out),

shouldn´t the new sequence be, after Tb, CH1, CH1(with trigger), CH5,CH3, where CH3 is the first one to be converted when the next trigger occurs?

Could you please explain this to me? I don't undestand why the new sequence is CH5, CH3, CH1, CH1 (with trigger) as shown in Figure 8 and Figure 9.

2) In second place, I can see from the example code that the external trigger for CH1 and CH0 s the same (trigger input A),

what is the sense of this ? .. or to put it in another way.. what would be different in terms of channel sampling order if CH0 wouln't have the Trigger activatated?

this is, if the sequence would be : CH1, CH1(with interrupt), CH5,CH3, CH0(without interrupt), where CH0 is the first channel to be sampled.

Isn't the trigger of CH0 redundant?

and now it comes the third question

3) How can I assigned a different trigger to CH0? so there is one external trigger to CH1, and a different onee to CH0.

Thank you very much for your time.

Regards.

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