Samsung KS57C2308 manual SMB Select Memory Bank, Smb, Addresses Register Areas Bank

SAM47 INSTRUCTION SET KS57C2308/P2308/C2316/P2316

SMB — Select Memory Bank

SMB	n
Operation:	Operand	Operation Summary	Bytes	Cycles
	n	Select memory bank	2	2

Description: The SMB instruction sets the upper four bits of a 12-bit data memory address to select a specific memory bank. The constants 0, n, and 15 are usually used as the SMB operand to select the corresponding memory bank. All references to data memory addresses fall within the following address ranges:

Please note that since data memory spaces differ for various devices in the SAM47 product family, the “n” value of the SMB instruction will also vary.

Addresses	Register Areas	Bank	SMB
000H–01FH	Working registers	0	0
020H–0FFH	Stack and general-purpose registers
n00H–7FFH	General-purpose registers	n	n
		(n = 1–14)	(n = 1–14)
F80H–FFFH	I/O-mapped hardware registers	15	15

The enable memory bank (EMB) flag must always be set to "1" in order for the SMB instruction to execute successfully for memory banks 0–15.

Format				Binary Code						Operation Notation
n	1	1	0		1	1	1	0	1	SMB ← n
	0	1	0		0	d3	d2	d1	d0

Example: If the EMB flag is set, the instruction

SMB 0

selects the data memory address range for bank 0 (000H–0FFH) as the working memory bank.

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