
137
6384E–ATARM–05-Feb-10
AT91SAM9G20
20.3
I/O Lines Description
Table 20-1.
EBI I/O Lines Description
Name
Function
Type
Active Level
EBI
EBI_D0 - EBI_D31
Data Bus
I/O
EBI_A0 - EBI_A25
Address Bus
Output
EBI_NWAIT
External Wait Signal
Input
Low
SMC
EBI_NCS0 - EBI_NCS7
Chip Select Lines
Output
Low
EBI_NWR0 - EBI_NWR3
Write Signals
Output
Low
EBI_NRD
Read Signal
Output
Low
EBI_NWE
Write Enable
Output
Low
EBI_NBS0 - EBI_NBS3
Byte Mask Signals
Output
Low
EBI for CompactFlash Support
EBI_CFCE1 - EBI_CFCE2
CompactFlash Chip Enable
Output
Low
EBI_CFOE
CompactFlash Output Enable
Output
Low
EBI_CFWE
CompactFlash Write Enable
Output
Low
EBI_CFIOR
CompactFlash I/O Read Signal
Output
Low
EBI_CFIOW
CompactFlash I/O Write Signal
Output
Low
EBI_CFRNW
CompactFlash Read Not Write Signal
Output
EBI_CFCS0 - EBI_CFCS1
CompactFlash Chip Select Lines
Output
Low
EBI for NAND Flash Support
EBI_NANDCS
NAND Flash Chip Select Line
Output
Low
EBI_NANDOE
NAND Flash Output Enable
Output
Low
EBI_NANDWE
NAND Flash Write Enable
Output
Low
SDRAM Controller
EBI_SDCK
SDRAM Clock
Output
EBI_SDCKE
SDRAM Clock Enable
Output
High
EBI_SDCS
SDRAM Controller Chip Select Line
Output
Low
EBI_BA0 - EBI_BA1
Bank Select
Output
EBI_SDWE
SDRAM Write Enable
Output
Low
EBI_RAS - EBI_CAS
Row and Column Signal
Output
Low
EBI_NWR0 - EBI_NWR3
Write Signals
Output
Low
EBI_NBS0 - EBI_NBS3
Byte Mask Signals
Output
Low
EBI_SDA10
SDRAM Address 10 Line
Output