Memory areas

The default initial values are 0 or FALSE.

Availability of memory areas:

The FP series PLCs have many different memory areas, which support 1-bit, 16-bit, or 32-bit addressing. Availability of the memory areas varies, depending on the PLC's processor. Addresses may be specified in FP format (e.g. X) or IEC format (%IX).

Memory area	1-bit	16-bit	32-bit	16-bit PLCs	32-bit PLCs
Input	X	WX	DXW	●	●
Output	Y	WY	DYW	●	●
Internal relay	R	WR	DWR	●	●
Timer relay	T			●	●¹⁾
Timer set value register		SV		●
Timer set value register			TSV		●¹⁾
Timer elapsed value register		EV		●
Timer elapsed value register			TEV		●¹⁾
Counter relay	C			●	●¹⁾
Counter set value register		SV		●
Counter set value register			CSV		●¹⁾
Counter elapsed value register		EV		●
Counter elapsed value register			CEV		●¹⁾
Data register		DT	DDT	●	●
File register		FL	DFL	●	●
Link relay	L	WL	DWL	●	●
Link register		LD		●
Link register			DLD		●
System relay	SR	WSR	DWS		●
System data		SD			●
System data			DSD
Unit memory		Sx:UM	Sx:DUM		●
Index register		IX		●
Index register			DIX		●
Error alarm relay	E			●	●
Pulse relay	P			●

¹⁾On the FP7, these addresses are reserved for the system.