User’s Manual
C166S V1 SubSystem
Central Processing Unit
User’s Manual
3-89
V 1.6, 2001-08
3.9
Dedicated CSFRs
The Constant Zeros Register ZEROS
All bits of this bit-addressable register are fixed at 0 by hardware. This register is read-
only. Register ZEROS can be used as a register-addressable constant of all zeros for bit
manipulation or mask generation. It can be accessed via any instruction capable of
accessing an SFR.
The Constant Ones Register ONES
All bits of this bit-addressable register are fixed at 1 by hardware. This register is read-
only. Register ONES can be used as a register-addressable constant of all ones for bit
manipulation or mask generation. It can be accessed via any instruction which is capable
of accessing an SFR.
Zeros
Constant Zeros Register
SFR(FF1C
H
,8E
H
)
Reset value: 0000
H
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
r
r
r
r
r
r
r
r
r
r
r
r
r
r
r
r
Field
Bits
Type Description
0
[all]
r
Fixed at Zero
ONES
Constant Ones Register
SFR(FF1E
H
,8F
H
)
Reset value: FFFF
H
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
r
r
r
r
r
r
r
r
r
r
r
r
r
r
r
r
Field
Bits
Type Description
1
[all]
r
Fixed at 1
Содержание C166S V1 SubSystem
Страница 10: ...User s Manual C166S V1 SubSystem User s Manual I 6 V 1 6 2001 08...
Страница 16: ...User s Manual C166S V1 SubSystem Introduction User s Manual 1 6 V 1 6 2001 08...
Страница 126: ...User s Manual C166S V1 SubSystem Central Processing Unit User s Manual 3 96 V 1 6 2001 08...
Страница 178: ...User s Manual C166S V1 SubSystem Memory Organization User s Manual 4 52 V 1 6 2001 08...
Страница 206: ...User s Manual C166S V1 SubSystem Instruction Set User s Manual 5 28 V 1 6 2001 08...
Страница 306: ...User s Manual C166S V1 SubSystem Detailed Instruction Set User s Manual 6 100 V 1 6 2001 08...
Страница 362: ...User s Manual C166S V1 SubSystem The External Bus Interface User s Manual 8 40 V 1 6 2001 08...
Страница 452: ...User s Manual C166S V1 SubSystem General Purpose Timer Unit User s Manual 12 44 V 1 6 2001 08...
Страница 454: ...User s Manual C166S V1 SubSystem Instruction Index User s Manual 13 2 V 1 6 2001 08...
Страница 459: ......