Renesas SH7041 Series, Hardware Manual, Page: 279 / 923

241
SAR3
DAR3
Data
buffer
Address b
us
Data b
us
Memory
Transfer source
module
Transfer destination
module
Temporary
buffer
The SAR3 value is taken as the address, memory data is read, and the value is stored in the
temporary buffer. Since the value read at this time is used as the address, it must be 32 bits.
When external connection data bus is 16 bits, two bus cycles are required.
DMAC
SAR3
DAR3
Data
buffer
Address b
us
Data b
us
Memory
Transfer source
module
Transfer destination
module
Temporary
buffer
The value in the temporary buffer is taken as the address, and data is read from the
transfer source module to the data buffer.
SAR3
DAR3
Data
buffer
Address b
us
Data b
us
Memory
Transfer source
module
Transfer destination
module
Temporary
buffer
The DAR3 value is taken as the address, and the value in the data buffer is written to the
transfer destination module.
Note: Memory, transfer source, and transfer destination modules are shown here.
In practice, connection can be made anywhere there is address space.
DMAC
DMAC
1st, 2nd bus cycles
3rd bus cycle
4th bus cycle
Figure 11.9 Dual Address Mode and Indirect Address Operation
(When External Memory Space is 16 bits)