11.1.1 Source and Destination

Using the DMA Controller, data may be moved between any two addresses in the Data Space. The SFR space (0000h to 0FFFh), or the data RAM space (1000h to 4FFFh), can serve as either the source or the destination. Data can be moved between these areas in either direction or between addresses in either area. The four different combinations are shown in Addressing Modes.

If it is necessary to protect areas of data RAM, the DMA Controller allows the user to set upper and lower address boundaries for operations in the Data Space above the SFR space. The boundaries are set by the DMAH and DMAL Limit registers. If a DMA channel attempts an operation outside of the address boundaries, the transaction is terminated and an interrupt is generated.