at91sam7x256 ATMEL Corporation, at91sam7x256 Datasheet - Page 16

• Manufacturer Part Number: at91sam7x256
• Description: Preliminary Summary
• Manufacturer: ATMEL Corporation

7.4
16
Peripheral DMA Controller
AT91SAM7X512/256/128 Preliminary
• Embedded Flash Controller
• Handles data transfer between peripherals and memories
• Thirteen channels
• Low bus arbitration overhead
• Next Pointer management for reducing interrupt latency requirements
• Peripheral DMA Controller (PDC) priority is as follows (from the highest priority to the lowest):
– Embedded Flash interface, up to three programmable wait states
– Prefetch buffer, buffering and anticipating the 16-bit requests, reducing the required
– Key-protected program, erase and lock/unlock sequencer
– Single command for erasing, programming and locking operations
– Interrupt generation in case of forbidden operation
– Two for each USART
– Two for the Debug Unit
– Two for the Serial Synchronous Controller
– Two for each Serial Peripheral Interface
– One for the Analog-to-digital Converter
– One Master Clock cycle needed for a transfer from memory to peripheral
– Two Master Clock cycles needed for a transfer from peripheral to memory
wait states
Receive
Receive
Receive
Receive
Receive
Receive
Receive
Transmit
Transmit
Transmit
Transmit
Transmit
Transmit
DBGU
USART0
USART1
SSC
ADC
SPI0
SPI1
DBGU
USART0
USART
SSC
SPI0
SPI1
6120ES–ATARM–08-Oct-07