		i	synthesize instructions events
		b	synthesize branches events
		c	synthesize branches events (calls only)
		r	synthesize branches events (returns only)
		x	synthesize transactions events
		e	synthesize error events
		d	create a debug log
		g	synthesize a call chain (use with i or x)

	The default is all events i.e. the same as --itrace=ibxe

	In addition, the period (default 100000) for instructions events
	can be specified in units of:

		i	instructions
		t	ticks
		ms	milliseconds
		us	microseconds
		ns	nanoseconds (default)

	Also the call chain size (default 16, max. 1024) for instructions or
	transactions events can be specified.