When triggered this block sends a delayed pulse
After a rising edge at the input Tr, the timer of the block is started. After the delay time D, the output Q is activated for the pulse duration which is set by T. The delay time D is restarted with each rising edge at the input Tr.
If the input R is activated, the timer is reset and the output Q is disabled. Then only after a new rising edge at the input Tr, will the timer be restarted.
The block can be set to be retentive, this is done by clicking on the battery symbol to set the red NOT dot on the block (input is by default inactive).