User’s Manual
C166S V1 SubSystem
The External Bus Interface
User’s Manual
8-15
V 1.6, 2001-08
Figure 8-7
Latched and Early Chip Select
Segment Address versus Chip Select
The external bus interface of the C166S supports many configurations for the external
memory. By increasing the number of segment address lines, the C166S can address a
linear address space of 256 KByte, 1 MByte, 4 MByte, 8 MByte or 16 MByte. This allows
implementation of a large sequential memory area, and access to a great number of
external devices, using an external decoder. By increasing the number of CS lines, the
C166S can access memory banks or peripherals without external glue logic. These two
features may be combined to optimize the overall system performance.
Note: If the number of segment address lines and CS lines configured at reset cause
overlap (e.g. A18...A16 and CS4...CS0), the segment address line function will
take precedence.
Valid
CSxE
CLKOUT
Normal ALE
Normal ALE Cycle
5)
CSxL
Extend. ALE
Extended ALE Cycle
5)
5)
Section 8.3.1
ALE Length Control
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...
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