SAM7SE256 Atmel Corporation, SAM7SE256 Datasheet - Page 173

• Manufacturer Part Number: SAM7SE256
• Manufacturer: Atmel Corporation

Specifications of SAM7SE256

• Flash (kbytes): 256 Kbytes
• Pin Count: 144
• Max. Operating Frequency: 48 MHz
• Cpu: ARM7TDMI
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 88
• Ext Interrupts: 88
• Usb Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 1
• Twi (i2c): 1
• Uart: 3
• Ssc: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 384
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 32
• Self Program Memory: NO
• External Bus Interface: 1
• Dram Memory: sdram
• Nand Interface: Yes
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8/3.3
• Operating Voltage (vcc): 3.0 to 3.6
• Fpu: No
• Mpu / Mmu: Yes / No
• Timers: 3
• Output Compare Channels: 3
• Input Capture Channels: 3
• Pwm Channels: 4
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: No

22.6.4.5
6222F–ATARM–14-Jan-11
Early Read Wait State
Figure 22-17. Chip Select Wait State
Notes:
In early read protocol, an early read wait state is automatically inserted when an external write
cycle is followed by a read cycle to allow time for the write cycle to end before the subsequent
read cycle begins (see
grammed wait states (i.e., data float wait state).
No wait state is added when a read cycle is followed by a write cycle, between consecutive
accesses of the same type, or between external and internal memory accesses.
Figure 22-18. Early Read Wait States
1. Early Read Protocol
2. Standard Read Protocol
A[22:0]
D[15:0]
NWE
MCK
A[22:0]
NCS1
NCS2
NRD
NWE
MCK
NRD
NCS
Figure
(1)
Write Cycle
addr Mem 1
22-18). This wait state is generated in addition to any other pro-
Mem 1
(2)
Early Read Wait
Chip Select Wait
addr Mem 2
SAM7SE512/256/32
Read Cycle
Mem 2
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