Abstract: The invention provides a direct memory access (DMA) controller. The DMA controller has an address register, a data register and transfer circuitry for transferring data over a bus of a computing system. The DMA controller is configured to use the transfer circuitry to read data over the bus from a memory location having a first memory address, wherein the data comprises a second memory address, and store the second memory address in the address register, and use the transfer circuitry to transfer data over the bus between a memory location having the second memory address, or having a memory address derived from the second memory address, and the data register.