M55800A Atmel Corporation, M55800A Datasheet - Page 50

• Manufacturer Part Number: M55800A
• Manufacturer: Atmel Corporation

Specifications of M55800A

• Flash (kbytes): 0 Kbytes
• Pin Count: 176
• Max. Operating Frequency: 33 MHz
• Cpu: ARM7TDMI
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 58
• Ext Interrupts: 58
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Uart: 3
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 72
• Resistive Touch Screen: No
• Dac Channels: 1
• Dac Resolution (bits): 10
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 8
• Self Program Memory: NO
• External Bus Interface: 1
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 3.3/5.0
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 6
• Output Compare Channels: 6
• Input Capture Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: No

PS: Power-saving
Peripheral Clocks
50
AT91X40 Series
The AT91X40 Series’ Power-saving feature enables optimization of power consumption.
The PS controls the CPU and Peripheral Clocks. One control register (PS_CR) enables
the user to stop the ARM7TDMI Clock and enter Idle Mode. One set of registers with a
set/clear mechanism enables and disables the peripheral clocks individually.
The ARM7TDMI clock is enabled after a reset and is automatically re-enabled by any
enabled interrupt in the Idle Mode.
The clock of each peripheral integrated in the AT91X40 Series can be individually
enabled and disabled by writing to the Peripheral Clock Enable (PS_PCER) and Periph-
eral Clock Disable Registers (PS_PCDR). The status of the peripheral clocks can be
read in the Peripheral Clock Status Register (PS_PCSR).
When a peripheral clock is disabled, the clock is immediately stopped. When the clock is
re-enabled, the peripheral resumes action where it left off.
To avoid data corruption or erroneous behavior of the system, the system software only
disables the clock after all programmed peripheral operations have finished.
The peripheral clocks are automatically enabled after a reset.
The bits that control the peripheral clocks are the same as those that control the Inter-
rupt Sources in the AIC.
1354D–ATARM–08/02