| 摘要 |
A direct memory access (DMA) controller for controlling memory access operations in a memory. During a memory access operation, the DMA controller executes a chain of DMA commands stored in a memory and having a respective address. The DMA controller can enter a self-linking mode where additional DMA commands can be appended to the end of the command chain without terminating the memory access operation, regardless of whether the last DMA command of the command chain has been executed by the DMA controller. The self-linking mode is entered when a link-address provided by the last DMA command matches a code. The code to cause the DMA controller to enter the self-linking mode may be a link address which points to the last executed DMA command, or alternatively, a predetermined bit pattern. The DMA controller exits the self-linking command and continues the memory access operation upon detecting a new link address for a new DMA command that is to be appended to the command chain. The new link address may be detected by having the DMA controller periodically check the link address of the last executed DMA command.
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