From a hardware perspective, the DDS registers can be programmed ahead of time and then the actual change of output freq/phase/amplitude occurs when the IO_UPDATE (aka FUD) command is sent. So if multiple DDS chips need to be updated to new output parameters at the same time, one would program them one at a time over the DDS parallel bus, then send them all a common IO_UPDATE signal at the appropriate time for the update to happen.
On the QC1 hardware, there is no possibility to send a common FUD. When programming several DDSes in a batch, the core device will issue tight programming+FUD sequences and compensate each POW for the dispersion in FUD times.
Sebastien _______________________________________________ ARTIQ mailing list https://ssl.serverraum.org/lists/listinfo/artiq
