at91sam9263 ATMEL Corporation, at91sam9263 Datasheet - Page 278

• Manufacturer Part Number: at91sam9263
• Description: At91 Arm Thumb Microcontrollers
• Manufacturer: ATMEL Corporation

Figure 24-5. Multi-block Transfer Using Linked Lists
Table 24-2.
6249D–ATARM–20-Dec-07
Transfer Type
1) Single Block or
last transfer of
multi-Block
2) AutoReload
multi-block transfer
with contiguous
SAR
3) AutoReload
multi-block transfer
with contiguous
DAR
4) AutoReload
multi-block transfer
LLPx(0)
Programming of Transfer Types and Channel Register Update Method (DMAC State Machine Table)
LLP.
LOC
= 0
Yes
Yes
Yes
Yes
CTLx[63..32]
CTLx[31..0]
LLPx(1)
DARx
SARx
DMAC block chaining is supported by using a Linked List Pointer register (DMAC_LLPx) that
stores the address in memory of the next linked list item. Each LLI (block descriptor) contains
the corresponding block descriptor (DMAC_SARx, DMAC_DARx, DMAC_LLPx, DMAC_CTLx).
To set up block chaining, a sequence of linked lists must be programmed in memory.
The DMAC_SARx, DMAC_DARx, DMAC_LLPx and DMAC_CTLx registers are fetched from
system memory on an LLI update.
lists in memory to define multi-block transfers using block chaining.
The Linked List multi-block transfers is initiated by programming DMAC_LLPx with LLPx(0)
( L L I ( 0 ) b a s e a d d r e s s ) a n d D M AC _ C T L x w i t h D M A C _ C T L x . L L P _ S _ E N a n d
DMAC_CTLx.LLP_D_EN.
LLP_S_EN
(DMAC_
CTLx)
0
0
0
0
LLI(0)
RELOAD
_SR
(DMAC_
CFGx)
0
0
1
1
System Memory
LLP_D_EN
(DMAC_
CTLx)
0
0
0
0
LLPx(1)
Figure 24-8 on page 286
RELOAD_
DS
(DMAC_
CFGx)
0
1
0
1
CTLx[63..32]
CTLx[31..0]
LLPx(2)
DARx
SARx
AT91SAM9263 Preliminary
LLI(1)
DMAC_CTLx,
DMAC_LLPx
Update
Method
None, user
reprograms
DMAC_CTLx,D
MAC_LLPx are
reloaded from
initial values.
DMAC_CTLx,D
MAC_LLPx are
reloaded from
initial values.
DMAC_CTLx,D
MAC_LLPx are
reloaded from
initial values.
shows how to use chained linked
DMAC_SARx
Update
Method
None (single)
Contiguous
Auto-Reload
Auto-Reload
LLPx(2)
DMAC_
DARx
Update
Method
None
(single)
Auto-
Reload
Con-
tiguous
Auto-
Reload
–
–
–
–
–
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