User's Manual

Rev.1.10 Jul 01, 2005 page 88 of 318
REJ09B0124-0110
M16C/6N Group (M16C/6NK, M16C/6NM) 11. DMAC
Under development
This document is under development and its contents are subject to change.
Figure 11.5 Transfer Cycles for Source Read
NOTE:
1. The same timing changes occur with the respective conditions at the destination as at the source.
(1) When the transfer unit is 8 or 16 bits and the source of transfer is an even address
BCLK
Address
bus
RD signal
WR signal
Data
bus
CPU use
CPU use CPU use
CPU useSource
Source
Destination
Destination
Dummy
cycle
Dummy
cycle
(2) When the transfer unit is 16 bits and the source address of transfer is an odd address, or when the
transfer unit is 16 bits and an 8-bit bus is used
BCLK
Address
bus
RD signal
WR signal
Data
bus
CPU use
CPU use CPU use
CPU useSource
Source
Destination
Destination
Dummy
cycle
Dummy
cycle
Source + 1
Source + 1
(3) When the source read cycle under condition (1) has one wait state inserted
BCLK
Address
bus
RD signal
WR signal
Data
bus
CPU use
CPU use CPU use
CPU use
Source
Source
Destination
Destination
Dummy
cycle
Dummy
cycle
(4) When the source read cycle under condition (2) has one wait state inserted
BCLK
Address
bus
RD signal
WR signal
Data
bus
CPU use
CPU use CPU use
CPU useSource
Source
Destination
Destination
Dummy
cycle
Dummy
cycle
Source + 1
Source + 1