A-99
INSTRUCTION SET REFERENCE
Example:
The MCS 251 controller is operating in nonpage mode. An external 256-byte RAM using
multiplexed address/data lines (e.g., an Intel 8155 RAM/I/O/Timer) is connected to port 0.
Port 3 provides control lines for the external RAM. ports 1 and 2 are used for normal I/O. R0
and R1 contain 12H and 34H. Location 34H of the external RAM contains 56H. After
executing the instruction sequence
MOVX A,@R1
MOVX @R0,A
the accumulator and external RAM location 12H contain 56H.
Variations
MOVX A,@DPTR
Binary Mode
Source Mode
Bytes:
1
1
States:
5
5
Hex Code in:
Binary Mode = [Encoding]
Source Mode = [Encoding]
Operation:
MOVX
(A)
←
((DPTR))
MOVX A,@Ri
Binary Mode
Source Mode
Bytes:
1
1
States:
3
3
Hex Code in:
Binary Mode = [Encoding]
Source Mode = [A5][Encoding]
Operation:
MOVX
(A)
←
((Ri))
MOVX @DPTR,A
Binary Mode
Source Mode
Bytes:
1
1
States:
5
5
Hex Code in:
Binary Mode = [Encoding]
Source Mode = [Encoding]
Operation:
MOVX
((DPTR))
←
(A)
[Encoding]
1 1 1 0
0 0 0 0
[Encoding]
1 1 1 0
0 0 1 i
[Encoding]
1 1 1 1
0 0 0 0
Содержание 8XC251SA
Страница 2: ......
Страница 3: ...May 1996 8XC251SA 8XC251SB 8XC251SP 8XC251SQ Embedded Microcontroller User s Manual...
Страница 18: ......
Страница 19: ...1 Guide to This Manual...
Страница 20: ......
Страница 30: ......
Страница 31: ...2 Architectural Overview...
Страница 32: ......
Страница 41: ...3 Address Spaces...
Страница 42: ......
Страница 63: ...4 Device Configuration...
Страница 64: ......
Страница 81: ...5 Programming...
Страница 82: ......
Страница 102: ......
Страница 103: ...6 Interrupt System...
Страница 104: ......
Страница 120: ......
Страница 121: ...7 Input Output Ports...
Страница 122: ......
Страница 132: ......
Страница 133: ...8 Timer Counters and Watchdog Timer...
Страница 134: ......
Страница 153: ...9 Programmable Counter Array...
Страница 154: ......
Страница 170: ......
Страница 171: ...10 Serial I O Port...
Страница 172: ......
Страница 187: ...11 Minimum Hardware Setup...
Страница 188: ......
Страница 197: ...12 Special Operating Modes...
Страница 198: ......
Страница 206: ......
Страница 207: ...13 External Memory Interface...
Страница 208: ......
Страница 239: ...14 Programming and Verifying Nonvolatile Memory...
Страница 240: ......
Страница 250: ......
Страница 251: ...A Instruction Set Reference...
Страница 252: ......
Страница 390: ......
Страница 391: ...B Signal Descriptions...
Страница 392: ......
Страница 400: ......
Страница 401: ...C Registers...
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Страница 436: ......
Страница 437: ...Glossary...
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Страница 446: ......
Страница 447: ...Index...
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