SAM3X8C Atmel Corporation, SAM3X8C Datasheet - Page 437

• Manufacturer Part Number: SAM3X8C
• Manufacturer: Atmel Corporation

26.9.2.1
26.9.2.2
11057A–ATARM–17-Feb-12
11057A–ATARM–17-Feb-12
Byte Write Access
Byte Select Access
Figure 26-5.
Byte write access supports one byte write signal per byte of the data bus and a single read
signal.
Note that the SMC does not allow boot in Byte Write Access mode.
In this mode, read/write operations can be enabled/disabled at byte level. One byte-select line
per byte of the data bus is provided. One NRD and one NWE signal control read and write.
• For 16-bit devices: the SMC provides NWR0 and NWR1 write signals for respectively, byte0
• For 16-bit devices: the SMC provides NBS0 and NBS1 selection signals for respectively
(lower byte) and byte1 (upper byte) of a 16-bit bus. One single read signal (NRD) is provided.
byte0 (lower byte) and byte1 (upper byte) of a 16-bit bus.
Byte Write Access is used to connect 2 x 8-bit devices as a 16-bit memory.
Byte Select Access is used to connect one 16-bit device.
Memory Connection for a 16-bit Data Bus
SMC
D[15:0]
NCS[2]
A[19:2]
NBS0
NBS1
NWE
NRD
A1
D[15:0]
A[18:1]
A[0]
Low Byte Enable
High Byte Enable
Write Enable
Output Enable
Memory Enable
SAM3X/A
SAM3X/A
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