SAM7L128 Atmel Corporation, SAM7L128 Datasheet - Page 179

• Manufacturer Part Number: SAM7L128
• Manufacturer: Atmel Corporation

Specifications of SAM7L128

• Flash (kbytes): 128 Kbytes
• Pin Count: 144
• Max. Operating Frequency: 36 MHz
• Cpu: ARM7TDMI
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 80
• Ext Interrupts: 80
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Uart: 3
• Segment Lcd: 40
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 4
• Adc Resolution (bits): 10
• Adc Speed (ksps): 460
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 6
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8/3.3
• Operating Voltage (vcc): 1.8 to 3.6
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 3
• Output Compare Channels: 3
• Input Capture Channels: 3
• Pwm Channels: 4
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: No

22. Peripheral DMA Controller (PDC)
22.1
22.2
6257A–ATARM–20-Feb-08
Overview
Block Diagram
The Peripheral DMA Controller (PDC) transfers data between on-chip serial peripherals such as
the UART, USART, SSC, SPI, MCI and the on- and off-chip memories. Using the Peripheral
DMA Controller avoids processor intervention and removes the processor interrupt-handling
overhead. This significantly reduces the number of clock cycles required for a data transfer and,
as a result, improves the performance of the microcontroller and makes it more power efficient.
The PDC channels are implemented in pairs, each pair being dedicated to a particular periph-
eral. One channel in the pair is dedicated to the receiving channel and one to the transmitting
channel of each UART, USART, SSC and SPI.
The user interface of a PDC channel is integrated in the memory space of each peripheral. It
contains:
The peripheral triggers PDC transfers using transmit and receive signals. When the pro-
grammed data is transferred, an end of transfer interrupt is generated by the corresponding
peripheral.
Figure 22-1. Block Diagram
• two 32-bit memory pointer registers (send and receive)
• two 16-bit transfer count registers (send and receive)
• two 32-bit registers for next memory pointer (send and receive)
• two 16-bit registesr for next transfer count (send and receive)
Peripheral
Control
THR
RHR
AT91SAM7L128/64 Preliminary
Status & Control
PDC Channel 0
PDC Channel 1
Peripheral DMA Controller
Control
Controller
Memory
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