SAM9XE512 Atmel Corporation, SAM9XE512 Datasheet - Page 202

• Manufacturer Part Number: SAM9XE512
• Manufacturer: Atmel Corporation

Specifications of SAM9XE512

• Flash (kbytes): 512 Kbytes
• Pin Count: 217
• Max. Operating Frequency: 180 MHz
• Cpu: ARM926
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 96
• Ext Interrupts: 96
• Usb Transceiver: 3
• Usb Speed: Full Speed
• Usb Interface: Host, Device
• Spi: 2
• Twi (i2c): 2
• Uart: 6
• Ssc: 1
• Ethernet: 1
• Sd / Emmc: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: Yes
• Adc Channels: 4
• Adc Resolution (bits): 10
• Adc Speed (ksps): 312
• 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): 1.65 to 1.95
• Fpu: No
• Mpu / Mmu: No / Yes
• Timers: 6
• Output Compare Channels: 6
• Input Capture Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: No

23.8
23.8.1
23.8.1.1
202
Standard Read and Write Protocols
AT91SAM9XE128/256/512 Preliminary
Read Waveforms
NRD Waveform
In the following sections, the byte access type is not considered. Byte select lines (NBS0 to
NBS3) always have the same timing as the A address bus. NWE represents either the NWE sig-
nal in byte select access type or one of the byte write lines (NWR0 to NWR3) in byte write
access type. NWR0 to NWR3 have the same timings and protocol as NWE. In the same way,
NCS represents one of the NCS[0..7] chip select lines.
The read cycle is shown on
The read cycle starts with the address setting on the memory address bus, i.e.:
Figure 23-8. Standard Read Cycle
The NRD signal is characterized by a setup timing, a pulse width and a hold timing.
1. NRD_SETUP: the NRD setup time is defined as the setup of address before the NRD
2. NRD_PULSE: the NRD pulse length is the time between NRD falling edge and NRD
3. NRD_HOLD: the NRD hold time is defined as the hold time of address after the NRD
NBS0,NBS1,
NBS2,NBS3,
A0, A1
falling edge;
rising edge;
rising edge.
{A[25:2], A1, A0} for 8-bit devices
{A[25:2], A1} for 16-bit devices
A[25:2] for 32-bit devices.
D[31:0]
A[25:2]
MCK
NRD
NCS
NCS_RD_SETUP
NRD_SETUP
Figure
23-8.
NCS_RD_PULSE
NRD_CYCLE
NRD_PULSE
NRD_HOLD
NCS_RD_HOLD
6254C–ATARM–22-Jan-10