Section 3 MCU Operating Modes
Rev.2.00 Jun. 28, 2007 Page 64 of 666
REJ09B0311-0200
3.2.2
System Control Register (SYSCR)
SYSCR controls MAC saturation operation, selects bus width mode for instruction fetch, sets
external bus mode, enables/disables the on-chip RAM, and selects the DTC address mode.
Bit
Bit Name
Initial Value
R/W
Note:
*
The initial value depends on the startup mode.
15
1
R/W
14
1
R/W
13
MACS
0
R/W
12
1
R/W
11
FETCHMD
0
R/W
10
0
R/W
9
EXPE
Undefined
*
R/W
8
RAME
1
R/W
Bit
Bit Name
Initial Value
R/W
7
0
R/W
6
0
R/W
5
0
R/W
4
0
R/W
3
0
R/W
2
0
R/W
1
DTCMD
1
R/W
0
1
R/W
Bit Bit
Name
Initial
Value R/W Descriptions
15, 14
All
1
R/W
Reserved
These bits are always read as 1. The write value should
always be 1.
13
MACS
0
R/W
MAC Saturation Operation Control
Selects either saturation operation or non-saturation
operation for the MAC instruction.
0: MAC instruction is non-saturation operation
1: MAC instruction is saturation operation
12
1 R/W
Reserved
This bit is always read as 1. The write value should
always be 1.
11
FETCHMD 0
R/W
Instruction Fetch Mode Select
The H8SX CPU has two modes for instruction fetch: 16-
bit and 32-bit modes. It is recommended that the mode
should be set according to the bus width of the memory in
which the program is stored
*
1
.
0: 32-bit width
1: 16-bit width
Содержание H8SX/1650
Страница 2: ...Rev 2 00 Jun 28 2007 Page ii of xxii...
Страница 106: ...Section 4 Exception Handling Rev 2 00 Jun 28 2007 Page 84 of 666 REJ09B0311 0200...
Страница 142: ...Section 5 Interrupt Controller Rev 2 00 Jun 28 2007 Page 120 of 666 REJ09B0311 0200...
Страница 326: ...Section 8 I O Ports Rev 2 00 Jun 28 2007 Page 304 of 666 REJ09B0311 0200...
Страница 470: ...Section 12 Watchdog Timer WDT Rev 2 00 Jun 28 2007 Page 448 of 666 REJ09B0311 0200...
Страница 546: ...Section 13 Serial Communication Interface SCI Rev 2 00 Jun 28 2007 Page 524 of 666 REJ09B0311 0200...
Страница 566: ...Section 14 A D Converter Rev 2 00 Jun 28 2007 Page 544 of 666 REJ09B0311 0200...
Страница 574: ...Section 16 RAM Rev 2 00 Jun 28 2007 Page 552 of 666 REJ09B0311 0200...
Страница 584: ...Section 17 Clock Pulse Generator Rev 2 00 Jun 28 2007 Page 562 of 666 REJ09B0311 0200...
Страница 638: ...Section 19 List of Registers Rev 2 00 Jun 28 2007 Page 616 of 666 REJ09B0311 0200...
Страница 668: ...Section 20 Electrical Characteristics Rev 2 00 Jun 28 2007 Page 646 of 666 REJ09B0311 0200...
Страница 676: ...Appendix Rev 2 00 Jun 28 2007 Page 654 of 666 REJ09B0311 0200...
Страница 688: ...Rev 2 00 Jun 28 2007 Page 666 of 666 REJ09B0311 0200...
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Страница 692: ...H8SX 1650 Group Hardware Manual...