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LH75400/01/10/11 (Preliminary) User's Guide
Direct Memory Access Controller
12.3.2.5 Current Source Registers
The Current Source Registers are 16-bit Read Only registers that hold the current value of
the source address pointer. The value in the registers is used as an AHB address in a
source-to-DMA data transfer over the AHB.
If the SoInc bit in the Control Register is set to '1', the value in the Current Source Registers
increments as data transfers from a source to the DMA. The value increments at the end
of the address phase of the AHB transfer by the HSIZE value.
If the SoInc bit is '0', the Current Source Register will hold the same value during the whole
DMA data transfer.
12.3.2.6 Current Destination Registers
The Current Destination Registers are 16-bit Read Only registers that hold the current
value of the destination address pointer. The value in the registers is used as an AHB
address in a DMA-to-destination data transfer over the AHB.
If the DeInc bit in the Control Register is set to '1', the value in the Current Destination Reg-
isters increments as data transfers from the DMA to a destination. The value increments
at the end of the address phase of the AHB transfer by the HSIZE value.
If the DeInc bit is '0', the Current Destination Register holds the same value during the
entire DMA data transfer.
12.3.2.7 Terminal Count Register
The Terminal Count Register is a 16-bit Read Only register that contains the number of
data units remaining in the current DMA transfer. The data unit is equal to the source-to-
DMA data width (byte, half-word or word).
The register value is decremented every time data is transferred to the DMA FIFO. When
the terminal count reaches zero, the FIFO content transfers to the destination and a DMA
transfer is finished.
7/15/03
12-11
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