User`s manual

To calculate combined list codes from NEGATIVE voltage values, use the
formula:
DAC Code = ((voltage value / .00125) shift left by 3) + 32768
For example, to output -2V:
DAC Code = ((-2 / .00125) shift left by 3) + 32768 = -12800 + 32768 = 19968
To calculate combined list codes from POSITIVE voltage values, use the
formula:
DAC Code = ((voltage value / .00125) shift left by 3) - 32768
For example, to output +5V:
DAC Code = ((5 / .00125) shift left by 3) - 32768 = 32000 - 32768 = -768
To output a marker at a particular point, add “2” to the combined list DAC
code value of the point. For example, to add a marker bit of a point with a
voltage value of 5 V:
Code = ((5 / .00125) shift left by 3) -32768) + 2 = 32000 - 32768 + 2 = -766
The COMBUNS program shows how to store a combined list (i.e., waveform
segment and/or marker bit of an arbitrary waveform) into the AFG’s segment
memory. The list is stored in the Unsigned number format. The data is
transferred to the AFG using the Indefinite Length Arbitrary Block Data
method. The example generates a 200 point +5 V to -5 V negative going ramp.
A marker is output at the zero crossing (or center) of the ramp.
246 High Speed Operation Chapter 7