Fujitsu FR60 Hardware Manual page 535

●
Rotation mode (ch.0 to ch.1 only)
When operation is enabled, the initial states have the same order that they would have in fixed mode, but at
the end of each transfer operation, the priority of the channels is reversed. Thus, if more than one transfer
request is outputted at the same time, the channel is switched after each transfer unit.
This mode is effective when continuous or burst transfer is set.
Figure 16.3-5 shows DMA transfer in rotation mode.
ch0 transfer request
ch1 transfer request
Bus operation
Transfer ch
ch0 transfer end
ch1 transfer end
■ Channel Group
Set the selection priority as explained in the table below.
Table 16.3-7 lists the settings for DMA selection priority.
Table 16.3-7 Setting DMA Selection Priority
MODE
Fixed
Rotation
Figure 16.3-5 DMA Transfer in Rotation Mode
CPU SA DA
ch1
Priority
ch0 > ch1
The initial state is the top row.
ch0 > ch1
If transfer occurs for the top row, the priority is
reversed.
ch0 < ch1
SA DA SA DA SA DA
ch0 ch0
ch1
Remarks
−
CPU
517