As an optional feature, the disk drive performs UNBUFFERED REZERO operation for 1->0 track seek command.
Setting up this jumper is as follows ;

Table 6-7 UNBUFFERED REZERO Jumper

	SZ124 PCB REV.
	REV.1 or 2 Layout		REV.3- Layout
	Primary	Optional	Primary	Optional
Jumper position
UNBUFFERED REZERO	Not implemented	Implemented	Not implemented	Implemented