Control Registers; Dma Source Address Registers 0 To 3 (Dsa0 To Dsa3); Dma Source Address Registers 0H To 3H (Dsa0H To Dsa3H) - Renesas NU85E Preliminary User's Manual

7.5 Control Registers

7.5.1 DMA source address registers 0 to 3 (DSA0 to DSA3)

These registers are used to set the DMA transfer source addresses (28 bits each) for DMA channels n (n = 0 to 3).
They are divided into two 16-bit registers, DSAnH and DSAnL, respectively.
Since they are two-stage FIFO-configuration buffer registers, the transfer source address of a new DMA transfer
can be set during a DMA transfer (See 7.6 Next Address Setting Function).
When a flyby transfer is set according to the TTYP bit of the DMA addressing control registers n (DADCn), the
external memory addresses are set by the DSAn registers. At this time, any settings of the DMA destination address
registers n (DDAn) are ignored.

(1) DMA source address registers 0H to 3H (DSA0H to DSA3H)

These registers can be read or written in 16-bit units.
Figure 7-1. DMA Source Address Registers 0H to 3H (DSA0H to DSA3H)
15 14 13
DSA0H IR 0 0
DSA1H IR 0 0
DSA2H IR 0 0
DSA3H IR 0 0
Bit position Bit name
15 IR
11 to 0 SA27 to
SA16
Caution Bits 14 to 12 of the DSA0H to DSA3H registers must be set to 0. The operation when these
bits are set to 1 is not guaranteed.
152
CHAPTER 7 DMAC
12 11 10 9 8 7
SA SA SA SA SA
0
27 26 25 24 23
SA SA SA SA SA
0
27 26 25 24 23
SA SA SA SA SA
0
27 26 25 24 23
SA SA SA SA SA
0
27 26 25 24 23
Specifies the DMA transfer source.
0: External memory or peripheral macro
1: RAM
Sets the DMA transfer source address (A27 to A16). During a DMA transfer, the next DMA
transfer source address is maintained. For a flyby transfer, the external memory address is
maintained.
Preliminary User's Manual A14874EJ3V0UM
6 5 4 3 2 1
SA SA SA SA SA SA
22 21 20 19 18 17
SA SA SA SA SA SA
22 21 20 19 18 17
SA SA SA SA SA SA
22 21 20 19 18 17
SA SA SA SA SA SA
22 21 20 19 18 17
Function
0
SA Address After reset
16 FFFFF082H Undefined
SA Address After reset
16 FFFFF08AH Undefined
SA Address After reset
16 FFFFF092H Undefined
SA Address After reset
16 FFFFF09AH Undefined