CHAPTER 6 DMA FUNCTIONS (DMA CONTROLLER)
140
User’s Manual U14492EJ3V0UD
6.3
Control Registers
6.3.1 DMA source address registers 0 to 3 (DSA0 to DSA3)
These registers are used to set the DMA source addresses (28 bits each) for DMA channel n (n = 0 to 3). They
are divided into two 16-bit registers, DSAnH and DSAnL.
Since these registers are 2-stage FIFO buffer registers, a new source address for DMA transfer can be specified
during DMA transfer (refer to
6.9 Next Address Setting Function
). In this case, if a new DSAn register is set, the
value set will be transferred to the slave register and enabled only if DMA transfer ends normally, and the TCn bit of
DMA channel control register n (DCHCn) has been set to 1 or the INITn bit of the DCHCn register has been set to 1 (n
= 0 to 3). However, take note that this value set will be disabled if the DSAn register is set with the Enn bit of the
DCHCn register cleared to 0 and DMA transfer prohibited.
(1) DMA source address registers 0H to 3H (DSA0H to DSA3H)
These registers can be read/written in 16-bit units.
Be sure to set bits 12 to 14 to 0. If they are set to 1, the operation is not guaranteed.
Caution
When setting an address of an on-chip peripheral I/O register for the source address, be
sure to specify an address between FFFF000H and FFFFFFFH. An address of the on-chip
peripheral I/O register image (3FFF000H to 3FFFFFFH) must not be specified.
15
IR
DSA0H
Address
FFFFF082H
Initial value
Undefined
14
0
13
0
12
0
11
SA27
10
SA26
9
SA25
8
SA24
7
SA23
6
SA22
5
SA21
4
SA20
3
SA19
2
SA18
1
SA17
0
SA16
IR
DSA1H
FFFFF08AH
Undefined
0
0
0
SA27 SA26 SA25 SA24 SA23 SA22 SA21 SA20 SA19 SA18 SA17 SA16
IR
DSA2H
FFFFF092H
Undefined
0
0
0
SA27 SA26 SA25 SA24 SA23 SA22 SA21 SA20 SA19 SA18 SA17 SA16
IR
DSA3H
FFFFF09AH
Undefined
0
0
0
SA27 SA26 SA25 SA24 SA23 SA22 SA21 SA20 SA19 SA18 SA17 SA16
Bit Position
Bit Name
Function
15
IR
Specifies the DMA source address.
0: External memory, on-chip peripheral I/O
1: Internal RAM
11 to 0
SA27 to
SA16
Sets the DMA source addresses (A27 to A16). During DMA transfer, it stores the next
DMA transfer source address.
Содержание V850E/IA1 mPD703116
Страница 2: ...2 User s Manual U14492EJ3V0UD MEMO...