HP 54710A User's Reference Manual page 324

Waveform Menu
Waveform
Waveform
Waveform allows you to store waveforms to one of the four nonvolatile
memories in the oscilloscope. Each waveform memory can hold up to 64K
points. Because some plug-ins can use more than one slot, it is possible that
a waveform can be longer than 64K points on a D model mainframe. In that
case, the stored waveform takes up multiple waveform memories.
Current memory
The current memory softkey shows the available memories or memory pairs.
If the waveform takes up to 64K points, all four memories are available. If the
waveform is greater than 64K but less than 128K, the available memories are
grouped together in pairs. The three possible memory pairs are m1 and m2,
m2 and m3, and m3 and m4. If the waveform is greater than 128K but less
than 256K, the available memories are grouped together into one large
memory.
When the display for an available memory is turned on, the bar below the
memory fills in and turns blue. (The default color is blue.) If the display
memory is turned off, an open white box (default color) is displayed.
Display
Display turns a memory location on and off. Memories are displayed in blue
(default color). If a channel or function display is also on and its display is
set to the channel default colors, any trace overlap is displayed in pink
(default color).
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