Limitations; Segment Length And Linear Playtime - Keysight M8195A User Manual

3 Sequencing
3.11

Limitations

3.11.1

Segment Length and Linear Playtime

142
Due to the type of memory technology and the implementation of the memory
interface, every physical address jump within the sample memory will reduce the
bandwidth at the memory interface. The drawing below shows such an address jump.
Memory Layout
Segment
A
Segment
B
Figure 56: Address jump within segments
To put the density of address jumps below a limit, a minimum segment length of 257
sample vectors (big segment) is required. Small segments (256 vectors down to 5
vectors) are also possible but then the Linear Playtime Requirement must be met.
Linear Playtime Requirement:
The playtime of at least 257 sample vectors (257 sync clock cycles) must be placed in
the sample memory in an ascending address order. When writing samples to a totally
cleared memory, the order of segments is the order of how these segments are written
to the memory.
Idle delay segments are also considered in computing the playtime. The corresponding
playtime in sample vectors is computed from the idle delay value. When the data
segments before and after the idle delay segment are adjacent in memory the playtime
is computed as the sum of all three segments.
The last adjacent segments in a sequence in sequence mode or the last adjacent
segments in a scenario in scenario mode can be shorter than 257 sample vectors in
total.
Keysight M8195A Revision 2 – Arbitrary Waveform Generator User's Guide
Address Jump