variable scale in Signal generator & Oscilloscope index.html

[tom.zhang]

Hi,

There a variable defined as

var scale = (params.local.trig_source == 0 ? params.local.scale_ch1 : params.local.scale_ch2);

in the Signal generator & Oscilloscope application's index.html file. However, This variable scale does not exist in the corresponding part of the PID controller & Oscilloscope index.html file. What is the purpose of this variable scale?

Thanks

[juanviera22]

In my experience working with the generator & Oscilloscope index.html scale_chx is meant to be a readonly param.

RP has an input attenuator set up by a jumper for each channel (2Vpp - 20 Vpp), but the aquisition will be the same at the ADC, so RP need a scale factor to digitally compensate the attenuation. Same thing for probe att.

if you change those params on the GUI, you will see different scale_chx for each combination. Like this

1x LV : scale_chx =1
10x LV: scale_chx = 10
1x HV: scale_chx = 2
10x HV: scale_chx = 20

Also, you need to use this scale to attenuate the trigger lvl you set on GUI, beacuse it is digitally set up with the amplificated values watched on GUI, and there is no att on controller.so to compensate this.

hope this helps, i'm sorry about my poor english

[juanviera22]

By the way:

var scale = (params.local.trig_source == 0 ? params.local.scale_ch1 : params.local.scale_ch2);

is a ternary conditional assignation.

If the trigger source is ch 1 (params.local.trig_source == 0) the scale is taken from ch1 params, or if it is ch2 (params.local.trig_source == 1) the scale is taken from ch1 params