M16C Datasheet, PDF (77/262 Pages) Mitsubishi Electric Semiconductor – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

DMAC
Preliminary Specifications REV.B
Mitsubishi microcomputers
Specifications in this manual are tentative and subject to change.
M16C / 6N Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
(1) 8-bit transfers
16-bit transfers from even address and the source address is even.
BCLK
Address
bus
CPU use
Source
Destination
Dummy
cycle
CPU use
RD signal
WR signal
Data
bus
CPU use
Source
Destination
Dummy
cycle
CPU use
(2) 16-bit transfers and the source address is odd
Transferring 16-bit data on an 8-bit data bus (In this case, there are also two destination write cycles).
BCLK
Address
bus
CPU use
Source
Source + 1 Destination
Dummy
cycle
CPU use
RD signal
WR signal
Data
bus
CPU use
Source
Source + 1 _Destination
Dummy
cycle
CPU use
(3) One wait is inserted into the source read under the conditions in (1)
BCLK
Address
bus
CPU use
Source
Destination
Dummy
cycle
RD signal
WR signal
Data
bus
CPU use
Source
Destination
Dummy
cycle
CPU use
CPU use
(4) One wait is inserted into the source read under the conditions in (2)
(When 16-bit data is transferred on an 8-bit data bus, there are two destination write cycles).
BCLK
Address
bus
CPU use
Source
Source + 1
Destination
Dummy
cycle
CPU use
RD signal
WR signal
Data
bus
CPU use
Source
Source + 1
Destination
Dummy
cycle
CPU use
Note: The same timing changes occur with the respective conditions at the destination as at the source.
Figure 7-5. Example of the transfer cycles for a source read
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