In trends how to pass 'step' value

I’m passing  data channel to pass trends. The RRD file get’s created fine. But does this support passing ’step’ value ?

This is what I’m using to pass trends :

xymon --debug xymonServer "data hostname.trends
[test.rrd] 

DS:PSK:GAUGE:600:0:U 133
DS:XYZ:GAUGE:600:0:U 133
DS:ABC:GAUGE:600:U:U 599”


This is what I tried :

xymon --debug xymonServer "data hostname.trends
[test.rrd] -s 60
DS:PSK:GAUGE:600:0:U 133
DS:XYZ:GAUGE:600:0:U 133
DS:ABC:GAUGE:600:U:U 599”

I tried both -s and —step options but does not seems to affect default value of 300 seconds. Any idea what should I use to configure step value.