AT91SAM9G10-EK Atmel, AT91SAM9G10-EK Datasheet - Page 142

• 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

21.6
21.6.1
21.6.2
21.6.3
21.6.4
21.6.5
142
Functional Description
AT91SAM9G10
Bus Multiplexing
Pull-up Control
Static Memory Controller
SDRAM Controller
CompactFlash Support
The EBI transfers data between the internal AHB Bus (handled by the Bus Matrix) and the exter-
nal memories or peripheral devices. It controls the waveforms and the parameters of the
external address, data and control busses and is composed of the following elements:
The EBI offers a complete set of control signals that share the 32-bit data lines, the address
lines of up to 26 bits and the control signals through a multiplex logic operating in function of the
memory area requests.
Multiplexing is specifically organized in order to guarantee the maintenance of the address and
output control lines at a stable state while no external access is being performed. Multiplexing is
also designed to respect the data float times defined in the Memory Controllers. Furthermore,
refresh cycles of the SDRAM are executed independently by the SDRAM Controller without
delaying the other external Memory Controller accesses.
The EBI_CSA register in the Bus Matrix User Interface permits enabling of on-chip pull-up resis-
tors on the data bus lines not multiplexed with the PIO Controller lines. The pull-up resistors are
enabled after reset. Setting the DBPUC bit disables the pull-up resistors on the D0 to D15 lines.
Enabling the pull-up resistor on the D16-D31 lines can be performed by programming the appro-
priate PIO controller.
For information on the Static Memory Controller, refer to the Static Memory Controller section.
For information on the SDRAM Controller, refer to the SDRAM section.
The External Bus Interface integrates circuitry that interfaces to CompactFlash devices.
The CompactFlash logic is driven by the Static Memory Controller (SMC) on the NCS4 and/or
NCS5 address space. Programming the CS4A and/or CS5A bit of the EBI_CSA Register to the
appropriate value enables this logic. For details on this register, refer to the Bus Matrix User
Interface section. Access to an external CompactFlash device is then made by accessing the
address space reserved to NCS4 and/or NCS5 (i.e., between 0x5000 0000 and 0x5FFF FFFF
for NCS4 and between 0x6000 0000 and 0x6FFF FFFF for NCS5).
All CompactFlash modes (Attribute Memory, Common Memory, I/O and True IDE) are sup-
ported but the signals _IOIS16 (I/O and True IDE modes) and _ATA SEL (True IDE mode) are
not handled.
• Static Memory Controller (SMC)
• SDRAM Controller (SDRAMC)
• A chip select assignment feature that assigns an AHB address space to the external devices
• A multiplex controller circuit that shares the pins between the different Memory Controllers
• Programmable CompactFlash support logic
• Programmable NAND Flash support logic
6462A–ATARM–03-Jun-09