Samsung KS57C2308 manual PSW Program Status Word, FB1H, FB0H, SC2-SC0 SC1 IS1 IS0 EMB ERB

MEMORY MAPKS57C2308/P2308/C2316/P2316

PSW — Program Status Word FB1H, FB0H

Bit

Identifier

RESET Value

Read/Write

Bit Addressing

C

SC2–SC0

7	6	5	4	3	2	1	0
C	SC2	SC1	SC0	IS1	IS0	EMB	ERB
(1)	0	0	0	0	0	0	0
R/W	R	R	R	R/W	R/W	R/W	R/W
(2)	8	8	8	1/4/8	1/4/8	1/4/8	1/4/8

Carry Flag

0No overflow or borrow condition exists

1An overflow or borrow condition does exist

Skip Condition Flags

0No skip condition exists; no direct manipulation of these bits is allowed

1A skip condition exists; no direct manipulation of these bits is allowed

IS1, IS0	Interrupt Status Flags
	0	0	Service all interrupt requests
	0	1	Service only the high-priority interrupt(s) as determined in the interrupt
			priority register (IPR)
	1	0	Do not service any more interrupt requests
	1	1	Undefined

EMB	Enable Data Memory Bank Flag
	0	Restrict program access to data memory to bank 15 (F80H–FFFH) and to
		the locations 000H–07FH in the bank 0 only
	1	Enable full access to data memory banks 0, 1, 2, and 15

ERB	Enable Register Bank Flag
	0	Select register bank 0 as working register area
	1	Select register banks 0, 1, 2, or 3 as working register area in accordance with
		the select register bank (SRB) instruction operand

NOTES:

1.The value of the carry flag after a RESET occurs during normal operation is undefined. If a RESET occurs during power-down mode (IDLE or STOP), the current value of the carry flag is retained.

2.The carry flag can only be addressed by a specific set of 1-bit manipulation instructions. See Section 2 for detailed information.

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