341
Bits 31 to 21—Reserved: These bits are always read as 0. The write value should always be 0.
Bit 20—Direct/Indirect Selection (DI): Selects direct address mode or indirect address mode in
channel 3.
This bit is only valid in CHCR3. Writing to this bit is invalid in CHCR0 to CHCR2; 0 is read if
this bit is read. The write value should always be 0. When using 16-byte transfer, direct address
mode must be specified. Operation is not guaranteed if indirect address mode is specified.
Bit 20: DI
Description
0
Direct address mode operation for channel 3
(Initial value)
1
Indirect address mode operation for channel 3
Bit 19—Source Address Reload Bit (RO): Selects whether the source address initial value is
reloaded in channel 2.
This bit is only valid in CHCR2. Writing to this bit is invalid in CHCR0, CHCR1, and CHCR3; 0
is read if this bit is read. The write value should always be 0. When using 16-byte transfer, this bit
must be cleared to 0, specifying non-reloading. Operation is not guaranteed if reloading is
specified.
Bit 19: RO
Description
0
Source address is not reloaded
(Initial value)
1
Source address is reloaded
Bit 18—Request Check Level Bit (RL): Specifies whether DRAK (
DREQ
acknowledge) signal
output is active-high or active-low.
This bit is only valid in CHCR0 and CHCR1. Writing to this bit is invalid in CHCR2 and
CHCR3; 0 is read if this bit is read. The write value should always be 0.
Bit 18: RL
Description
0
Active-low DRAK output
(Initial value)
1
Active-high DRAK output
Summary of Contents for SH7709S
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