tmp19a44fda TOSHIBA Semiconductor CORPORATION, tmp19a44fda Datasheet - Page 284

• Manufacturer Part Number: tmp19a44fda
• Description: 32bit Tx System Risc
• Manufacturer: TOSHIBA Semiconductor CORPORATION

DMA Controller (DMAC)
(6) Combinations of transfer modes
(7) Address changes
The DMAC can transfer data by combining each transfer mode as follows:
Address changes are broadly classified into three types: increases, decreases and fixed. The type of
address change can be specified for each source and destination address by using SAC and DAC in
the CCRn register. For a memory device, an increase, decrease or fixed can be specified. If a single
transfer is selected as a source or destination device, SAC or DAC in the CCRn register must be set
to "fixed."
If address increase or decrease is selected, the bit position for counting can be specified using
SACM or DACM in the DTCRn register. To specify the bit position for counting a source address,
SACM must be used, while DACM must be used to specify the bit position for a destination
address. Any of the bits 0, 4, 8, 12 and 16 can be specified as the bit position for address counting.
If 0 is selected, an address normally increases or decreases. By selecting bits 4, 8, 12 or 16, it is
possible to increase or decrease an address irregularly.
Examples of address changes are shown below.
Example 1: Monotonic increase for a source device and irregular increase for a destination device
Transfer
request
External
External
Internal
1st
2nd
3rd
4th
…
SAC: Address increase
DAC: Address increase
TrSiz: Transfer unit 32 bits
Source address:
Destination address:
SACM: 000 → counting to begin from bit 0 of the address counter
DACM: 001 → counting to begin from bit 4 of the address counter
0xA000_1000
0xA000_1004
0xA000_1008
0xA000_100C
(INTDREQn)
Edge/level
Falling edge
(DREQn)
(DREQn)
"L" level
"L" level
Source
⎯
TMP19A44 (rev1.3) 10-21
0xA000_1000
0xB000_0000
Address mode
0xB000_0000
0xB000_0010
0xB000_0020
0xB000_0030
Destination
…
Dual
Continuous
Single
Continuous
Single
Transfer method
TMP19A44
2010-04-01