Bus Interface
[AT91]

Collaboration diagram for Bus Interface:

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Detailed Description

External bus interface registers.

Chip Select Register
#define	EBI_CSR(i)   (EBI_BASE + i * 4)
	Chip select register address.
#define	EBI_DBW   0x00000003
	Masks data bus width.
#define	EBI_DBW_16   0x00000001
	16-bit data bus width
#define	EBI_DBW_8   0x00000002
	8-bit data bus width
#define	EBI_NWS   0x0000001C
	Masks number of wait states.
#define	EBI_NWS_1   0x00000000
	1 wait state
#define	EBI_NWS_2   0x00000004
	2 wait states
#define	EBI_NWS_3   0x00000008
	3 wait states
#define	EBI_NWS_4   0x0000000C
	4 wait states
#define	EBI_NWS_5   0x00000010
	5 wait states
#define	EBI_NWS_6   0x00000014
	6 wait states
#define	EBI_NWS_7   0x00000018
	7 wait states
#define	EBI_NWS_8   0x0000001C
	8 wait states
#define	EBI_WSE   0x00000020
	Wait state enable.
#define	EBI_PAGES   0x00000180
	Page size mask.
#define	EBI_PAGES_1M   0x00000000
	1 MByte page size
#define	EBI_PAGES_4M   0x00000080
	4 MBytes page size
#define	EBI_PAGES_16M   0x00000100
	16 MBytes page size
#define	EBI_PAGES_64M   0x00000180
	64 MBytes page size
#define	EBI_TDF   0x00000E00
	Masks data float output time clock cycles.
#define	EBI_TDF_0   0x00000000
	No added cycles.
#define	EBI_TDF_1   0x00000200
	1 cycle
#define	EBI_TDF_2   0x00000400
	2 cycles
#define	EBI_TDF_3   0x00000600
	3 cycles
#define	EBI_TDF_4   0x00000800
	4 cycles
#define	EBI_TDF_5   0x00000A00
	5 cycles
#define	EBI_TDF_6   0x00000C00
	6 cycles
#define	EBI_TDF_7   0x00000E00
	7 cycles
#define	EBI_BAT   0x00001000
	Byte access type.
#define	EBI_BAT_BYTE_WRITE   0x00000000
	Byte write access type.
#define	EBI_BAT_BYTE_SELECT   0x00001000
	Byte select access type.
#define	EBI_CSEN   0x00002000
	Chip select enable.
#define	EBI_BA   0xFFF00000
	Page base address mask.
Remap Control Register
#define	EBI_RCR   (EBI_BASE + 0x20)
	Remap control register address.
#define	EBI_RCB   0x00000001
	Remap command.
Memory Control Register
#define	EBI_MCR   (EBI_BASE + 0x24)
	Memory control register address.
#define	EBI_ALE   0x00000007
	Address line enable.
#define	EBI_ALE_16M   0x00000000
	16 Mbytes total address space
#define	EBI_ALE_8M   0x00000004
	8 Mbytes total address space
#define	EBI_ALE_4M   0x00000005
	4 Mbytes total address space
#define	EBI_ALE_2M   0x00000006
	2 Mbytes total address space
#define	EBI_ALE_1M   0x00000007
	1 Mbyte total address space
#define	EBI_DRP   0x00000010
	Data read protocol mask.
#define	EBI_DRP_STANDARD   0x00000000
	Standard read protocol.
#define	EBI_DRP_EARLY   0x00000010
	Early read protocol.

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