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
Содержание SH7709S
Страница 2: ...Hitachi SuperH RISC engine SH7709S Hardware Manual ADE 602 250 Rev 1 0 09 21 01 Hitachi Ltd ...
Страница 75: ...56 ...
Страница 107: ...88 ...
Страница 125: ...106 ...
Страница 139: ...120 ...
Страница 203: ...184 ...
Страница 245: ...226 ...
Страница 292: ...273 T1 CKIO A25 to A0 CSn RD WR RD D31 to D0 WEn D31 to D0 BS T2 Read Write Figure 10 6 Basic Timing of Basic Interface ...
Страница 323: ...304 Tp TRr TRrw TRrw CKIO CKE CSn RAS3U RAS3L CASU CASL RD WR Figure 10 28 Synchronous DRAM Auto Refresh Timing ...
Страница 411: ...392 ...
Страница 609: ...590 ...
Страница 635: ...616 ...
Страница 663: ...644 ...
Страница 679: ...660 ...