ChipShouter, the "deadtime" parameter issue

I have some doubts about the deadtime parameter, can anyone help to explain it?

This is my setup:
cs.pulse.width = 120 #120 nS pulse width
cs.pulse.repeat = 3 #3 pulses
cs.pulse.deadtime = 10 #10mS deadtime
cs.pulse = 1 #Trigger a pulse

Refer to the chipShouter python API example:

But,the actual waveform:

The “deadtime” looks like 51ms !

My ChipShouter Information:

So, what is the unit of deadtime?

It should be in milliseconds, but the code just uses delay_ms() for the timing, so that could be off. Is it consistent in that halving the set deadtime halves the recorded deadtime?