Atmel Xplained Evaluation Board AT32UC3A3-XPLD AT32UC3A3-XPLD データシート
製品コード
AT32UC3A3-XPLD
181
32072H–AVR32–10/2012
AT32UC3A3
Figure 15-3. Memory Connections for Six External Devices
15.6.3
Connection to External Devices
15.6.3.1
Data bus width
A data bus width of 8 or 16 bits can be selected for each chip select. This option is controlled by
the Data Bus Width field in the Mode Register (MODE.DBW) for the corresponding chip select.
the Data Bus Width field in the Mode Register (MODE.DBW) for the corresponding chip select.
shows how to connect a 512K x 8-bit memory on NCS2.
shows how to connect a 512K x 16-bit memory on NCS2.
15.6.3.2
Byte write or byte select access
Each chip select with a 16-bit data bus can operate with one of two different types of write
access: byte write or byte select access. This is controlled by the Byte Access Type bit in the
MODE register (MODE.BAT) for the corresponding chip select.
access: byte write or byte select access. This is controlled by the Byte Access Type bit in the
MODE register (MODE.BAT) for the corresponding chip select.
Figure 15-4. Memory Connection for an 8-bit Data Bus
NCS[0] - NCS[5]
NRD
NWE
A[AD_MSB:0]
D[15:0]
SMC
NCS5
NCS4
NCS3
NCS2
NCS1
NCS0
8 or 16
Memory Enable
Memory Enable
Memory Enable
Memory Enable
Memory Enable
Memory Enable
Output Enable
Write Enable
A[AD_MSB:0]
D[15:0] or D[7:0]
SMC
A0
NWE
NRD
NCS[2]
A0
Write Enable
Output Enable
Memory Enable
D[7:0]
D[7:0]
A[18:2]
A[18:2]
A1
A1