AT91SAM9G10-EK Atmel, AT91SAM9G10-EK Datasheet - Page 163

• Manufacturer Part Number: AT91SAM9G10-EK
• Description: KIT DEV FOR SAM9G10 ARM
• Manufacturer: Atmel
• Type: MCUr

Specifications of AT91SAM9G10-EK

• Contents: Board, Cables, Power Supply
• Silicon Manufacturer: Atmel
• Core Architecture: AVR
• Kit Contents: Board
• Svhc: No SVHC (15-Dec-2010)
• Mcu Supported Families: AT91SAM9G10, ARM926EJ-S
• Tool / Board Applications: Microcontroller
• Rohs Compliant: Yes
• For Use With/related Products: *
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

22.7.2.1
22.7.2.2
6462A–ATARM–03-Jun-09
Byte Write Access
Byte Select Access
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 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.
Figure 22-7
mode, on NCS3 (BAT = Byte Select Access).
• For 16-bit devices: the SMC provides NWR0 and NWR1 write signals for respectively byte0
• For 32-bit devices: NWR0, NWR1, NWR2 and NWR3, are the write signals of byte0 (lower
• For 16-bit devices: the SMC provides NBS0 and NBS1 selection signals for respectively
• For 32-bit devices: NBS0, NBS1, NBS2 and NBS3, are the selection signals of byte0 (lower
(lower byte) and byte1 (upper byte) of a 16-bit bus. One single read signal (NRD) is provided.
byte), byte1, byte2 and byte 3 (upper byte) respectively. One single read signal (NRD) is
provided.
byte0 (lower byte) and byte1 (upper byte) of a 16-bit bus.
byte), byte1, byte2 and byte 3 (upper byte) respectively. Byte Select Access is used to
connect two 16-bit devices.
Byte Write Access is used to connect 2 x 8-bit devices as a 16-bit memory.
Byte Write Access is used to connect 4 x 8-bit devices as a 32-bit memory.
Byte Write option is illustrated on
Byte Select Access is used to connect one 16-bit device.
shows how to connect two 16-bit devices on a 32-bit data bus in Byte Select Access
Figure
22-6.
AT91SAM9G10
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