AT91SAM9261-CJ-999 Atmel, AT91SAM9261-CJ-999 Datasheet - Page 215

• Manufacturer Part Number: AT91SAM9261-CJ-999
• Description: IC MCU ARM9 ULTRA LP 217LFBGA
• Manufacturer: Atmel
• Series: AT91SAMr

Specifications of AT91SAM9261-CJ-999

• Core Processor: ARM9
• Core Size: 16/32-Bit
• Speed: 190MHz
• Connectivity: EBI/EMI, I²C, MMC, SPI, SSC, UART/USART, USB
• Peripherals: DMA, LCD, POR, PWM, WDT
• Number Of I /o: 96
• Program Memory Size: 32KB (32K x 8)
• Program Memory Type: ROM
• Ram Size: 192K x 8
• Voltage - Supply (vcc/vdd): 1.08 V ~ 1.32 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 217-LFBGA
• For Use With: AT91SAM9261-EK - KIT EVAL FOR AT91SAM926EJ-SAT91SAM-ICE - EMULATOR FOR AT91 ARM7/ARM9
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Data Converters: -

22.6.2
Register:
Address:
Access Type:Read-write
Reset Value: 0x00000000
• COUNT: SDRAMC Refresh Timer Count
This 12-bit field is loaded into a timer that generates the refresh pulse. Each time the refresh pulse is generated, a refresh
burst is initiated. The value to be loaded depends on the SDRAMC clock frequency (MCK: Master Clock), the refresh rate
of the SDRAM device and the refresh burst length where 15.6 µs per row is a typical value for a burst of length one.
To refresh the SDRAM device, this 12-bit field must be written. If this condition is not satisfied, no refresh command is
issued and no refresh of the SDRAM device is carried out.
6062M–ATARM–23-Mar-09
31
23
15
–
–
–
7
SDRAMC Refresh Timer Register
SDRAMC_TR
0xFFFFEA04
30
22
14
–
–
–
6
29
21
13
–
–
–
5
28
20
12
–
–
–
4
COUNT
27
19
11
–
–
3
AT91SAM9261 Preliminary
26
18
10
–
–
2
COUNT
25
17
–
–
9
1
24
16
–
–
8
0
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