I'm a little confused in the use of the auto clear phase accumulator
and auto clear sweep accumulator bits.
A have few questions about this:
1.What is difference in the use of bits FR[12..15] and CRF[0..3]
and how to set these bits in the frequency sweep mode for one channel.
2. From the data sheet of AD9958/59 it follows that: "The automatic clearing function is
repeated for every subsequent I/O update or change in profile pins until the clear and release bits are reset
I/O update or change in profile pins via the serial port" (page 27).
It is not clear what kind of change in a profile pin have in mind.
For example consider "LINEAR SWEEP MODE ENABLE—NO-DWELL BIT SET" (Fig 38).
The signal P2 on profile pin changed twice during the sweep interval - (at point A, he rises and between points A and B, it falls).
It is logical to assume that clearing takes place only on the rising edge, but I would like to know exactly.
3. In the frequency sweep mode I use I/O update within sweep interval to change signal amplitude.
Does this mean that the phase accumulator (or sweep accumulator) will be immediately cleared?
Many thanks for your advice.