SAM7SE256 Atmel Corporation, SAM7SE256 Datasheet - Page 271

• 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

28. Clock Generator
28.1
28.2
28.3
28.3.1
6222F–ATARM–14-Jan-11
Overview
Slow Clock RC Oscillator
Main Oscillator
Main Oscillator Connections
The Clock Generator is made up of 1 PLL, a Main Oscillator, as well as an RC Oscillator.
It provides the following clocks:
The Clock Generator User Interface is embedded within the Power Management Controller and
is described in
The user has to take into account the possible drifts of the RC Oscillator. More details are given
in the section “DC Characteristics” of the product datasheet.
Figure 28-1
Figure 28-1. Main Oscillator Block Diagram
The Clock Generator integrates a Main Oscillator that is designed for a 3 to 20 MHz fundamental
crystal. The typical crystal connection is illustrated in
trical characteristics of the Main Oscillator, see the section “DC Characteristics” of the product
datasheet.
• SLCK, the Slow Clock, which is the only permanent clock within the system
• MAINCK is the output of the Main Oscillator
• PLLCK is the output of the Divider and PLL block
shows the Main Oscillator block diagram.
Section
Slow Clock
XOUT
SLCK
29.9. However, the Clock Generator registers are named CKGR_.
XIN
Main Clock
OSCOUNT
Frequency
Oscillator
MOSCEN
Oscillator
Counter
Counter
Main
Main
Figure
SAM7SE512/256/32
28-2. For further details on the elec-
Main Clock
MAINCK
MAINRDY
MOSCS
MAINF
271