AT32UC3C1512C Automotive Atmel Corporation, AT32UC3C1512C Automotive Datasheet - Page 309

• Manufacturer Part Number: AT32UC3C1512C Automotive
• Manufacturer: Atmel Corporation

9166C–AVR-08/11
•Byte write access
•Byte select access
Figure 18-5.
The byte write access mode 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.
The byte write access mode is used to connect two 8-bit devices as a 16-bit memory.
The byte write option is illustrated on
In this mode, read/write operations can be enabled/disabled at a 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. The 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
Figure 18-6 on page
310.
D[15:0]
A[18:1]
A[0]
Low Byte Enable
High Byte Enable
Write Enable
Output Enable
Memory Enable
AT32UC3C
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