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Document Title: [650x.txt (text file)]

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|                           Rockwell                           |
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|              666     5555555     000     X     X             |
|             6        5          0   0     X   X              |
|            6         5         0   0 0     X X               |
|            666666    555555    0  0  0      X                |
|            6     6         5   0 0   0     X X               |
|            6     6         5    0   0     X   X              |
|             66666    555555      000     X     X             |
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|     6501/2/3/4/5 MICROPROCESSOR Instruction Set Summary      |
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|                 M     M    OOOOO     SSSSS                   |
|                 MM   MM   O     O   S     S                  |
|                 M M M M   O     O   S                        |
|                 M  M  M   O     O    SSSSS                   |
|                 M     M   O     O         S                  |
|                 M     M   O     O   S     S                  |
|                 M     M    OOOOO     SSSSS                   |
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|Written by     Jonathan Bowen                                 |
|               Programming Research Group                     |
|               Oxford University Computing Laboratory         |
|               8-11 Keble Road                                |
|               Oxford OX1 3QD                                 |
|               England                                        |
|                                                              |
|               Tel +44-865-273840                             |
|                                                              |
|Created        September 1981                                 |
|Updated        April 1985                                     |
|Issue          1.3                Copyright (C) J.P.Bowen 1985|
----------------------------------------------------------------
----------------------------------------------------------------
|Mnem.|Op|NVBDIZC|A#ZBIRX@|~|Description           |Notes      |
|-----+--+-------+--------+-+----------------------+-----------|
|ADC s|6D|**---**| XxX  X |4|Add with Carry        |A=A+s+C   %|
|AND s|2D|*----*-| XxX  X |4|Logical AND           |A=A&s     %|
|ASL d|0E|*----**|  xx    |6|Arithmetic Shift Left |d={C,d,0}<-|
|ASLA |0A|*----**|X       |2|Arithmetic Shift Left |A={C,d,0}<-|
|BCC a|90|-------|     X  |2|Branch if Carry Clear |If C=0(4~)%|
|BCS a|B0|-------|     X  |2|Branch if Carry Set   |If C=1(4~)%|
|BEQ a|F0|-------|     X  |2|Branch if Equal       |If Z=1(4~)%|
|BIT s|2C|**---*-|  **    |4|Bit Test              |A&s        |
|BMI a|30|-------|     X  |2|Branch if Minus       |If N=1(4~)%|
|BNE a|D0|-------|     X  |2|Branch if Not Equal   |If Z=0(4~)%|
|BPL a|10|-------|     X  |2|Branch if Plus        |If N=0(4~)%|
|BRK  |00|--+-1--|    X   |7|Break  (-[S]={PC+2,P})|PC=[FFFEH] |
|BVC a|50|-------|     X  |2|Branch if Overflow Clr|If V=0(4~)%|
|BVS a|70|-------|     X  |2|Branch if Overflow Set|If V=1(4~)%|
|CLC  |18|------0|    X   |2|Clear Carry flag      |C=0        |
|CLD  |D8|---0---|    X   |2|Clear Decimal mode    |D=0        |
|CLI  |58|----0--|    X   |2|Clear Int. disable    |I=0        |
|CLV  |B8|-0-----|    X   |2|Clear Overflow flag   |V=0        |
|CMP s|CD|*----**| XxX  X |4|Compare               |A-s        |
|CPX s|EC|*----**| X**    |4|Compare index register|X-s        |
|CPY s|CC|*----**| X**    |4|Compare index register|Y-s        |
|DEC d|CE|*----*-|  xx    |6|Decrement             |d=d-1      |
|DEX  |CA|*----*-|    X   |2|Decrement index reg.  |X=X-1      |
|DEY  |88|*----*-|    X   |2|Decrement index reg.  |Y=Y-1      |
|EOR s|4D|*----*-| XxX  X |4|Logical Exclusive OR  |A=Axs     %|
|INC d|EE|*----*-|  xx    |6|Increment             |d=d+1      |
|INX  |E8|*----*-|    X   |2|Increment index reg.  |X=X+1      |
|INY  |C8|*----*-|    X   |2|Increment index reg.  |Y=Y+1      |
|JMP s|4C|-------|   *   X|3|Jump                  |          !|
|JSR s|20|-------|   *    |6|Jump to Subroutine    |-[S]=PC+2,!|
|LDA s|AD|*----*-| XxX  X |4|Load Accumulator      |A=s       %|
|LDX s|AE|*----*-| Xyy    |4|Load index register   |X=s       %|
|LDY s|AC|*----*-| Xxx    |4|Load index register   |Y=s       %|
|LSR d|4E|0----**|  xx    |6|Logical Shift Right   |d=->{0,d,C}|
|LSRA |4A|0----**|X       |2|Logical Shift Right   |A=->{0,A,C}|
|NOP  |EA|-------|    X   |2|No Operation          |           |
|ORA s|0D|*----*-| XxX  X |4|Logical Inclusive OR  |A=Avs      |
|PHA  |48|-------|    X   |3|Push Accumulator      |-[S]=A     |
|PHP  |08|-------|    X   |3|Push status register  |-[S]=P     |
|PLA  |68|-------|    X   |4|Pull Accumulator      |A=[S]+     |
|PLP  |28|*******|    X   |4|Pull Status Register  |P=[S]+     |
|ROL d|2E|*----**|  xx    |6|Rotate Left           |d={C,d}<-  |
|ROLA |2A|*----**|X       |2|Rotate Left Acc.      |A={C,A}<-  |
|ROR d|6E|*----**|  xx    |6|Rotate Right          |d=->{C,d}  |
|RORA |6A|*----**|X       |2|Rotate Right Acc.     |A=->{C,A}  |
|RTI  |40|*******|    X   |6|Return from Interrupt |{PC,P}=[S]+|
|RTS  |60|-------|    X   |6|Return from Subroutine|PC={[S]+}+1|
|SBC s|ED|*----**| XxX  X |4|Subtract with Carry   |A=A-s-C   %|
|SEC  |38|------1|    X   |2|Set Carry flag        |C=1        |
|SED  |F8|---1---|    X   |2|Set Decimal mode      |D=1        |
|SEI  |78|----1--|    X   |2|Set Interrupt disable |I=1        |
|STA d|8D|-------|  xX  X |4|Store Accumulator     |d=A        |
|STX d|8E|-------|  y*    |4|Store index register  |d=X        |
|STY d|8C|-------|  x*    |4|Store index register  |d=Y        |
|TAX  |AA|*----*-|    X   |2|Transfer Accumulator  |X=A        |
|TAY  |A8|*----*-|    X   |2|Transfer Accumulator  |Y=A        |
|TSX  |BA|*----*-|    X   |2|Transfer Stack Pointer|X=S        |
|TXA  |8A|*----*-|    X   |2|Transfer Index Reg.   |A=X        |
|TXS  |9A|-------|    X   |2|Transfer Index Reg.   |S=X        |
|TYA  |98|*----*-|    X   |2|Transfer Index Reg.   |A=Y        |
|-----+--+-------+--------+-+----------------------------------|
|     |XX|       |        |X|Hexadecimal opcode/no. of cycles  |
|--------+-------+--------+-+----------------------------------|
|        |-      |        | |Flag unaffected                   |
|        |*      |        | |Flag affected                     |
|        |0      |        | |Flag reset                        |
|        |1      |        | |Flag set                          |
|        |+      |        | |Flag set on stack                 |
|--------+-------+--------+-+----------------------------------|
| N      |N      |        | |Negative status (Bit 7)           |
| V      | V     |        | |Overflow status (Bit 6)           |
| B      |  B    |        | |Break command indicator (Bit 4)   |
| D      |   D   |        | |Decimal mode control (Bit 3)      |
| I      |    I  |        | |Interrupt disable control (Bit 2) |
| Z      |     Z |        | |Zero status (Bit 1)               |
| C      |      C|        | |Carry status (Bit 0)              |
----------------------------------------------------------------
----------------------------------------------------------------
|Mnemonic        |A#ZBIRX@|Description             |Opcode| ~s |
|----------------+--------+------------------------+------+----|
|                |X       |All mode(s) valid       |      |    |
|                |*       |Non-indexed mode valid  |      |    |
|                |x       |X/non-indexed mode valid|      |    |
|                |y       |Y/non-indexed mode valid|      |    |
|----------------+--------+------------------------+------+----|
|                |        |Add XXH to opcode       | +XXH |    |
|                |        |Subtract XXH from opcode| -XXH |    |
|                |        |Add X to no. of cycles  |      | +X |
|                |        |Subtract X from cycles  |      | -X |
|----------------+--------+------------------------+------+----|
| A              |A       |Accumulator             |      |    |
| #n             | #      |Immediate               | -04H | -2 |
| <n             |  *     |Zero page               | -08H | -1 |
| n              |  *     |Zero page (DIRECT mode) | -08H | -1 |
| n,X            |  x     |Zero page indexed (X)   | +08H | +0 |
| n,Y            |  y     |Zero Page indexed (Y)   | +08H | +0 |
| >nn            |   *    |Absolute                | +00H | +0 |
| nn             |   *    |Absolute (EXTEND mode)  | +00H | +0 |
| nn,X           |   x    |Absolute indexed (X)    | +10H | +0 |
| nn,Y           |   y    |Absolute indexed (Y)    | +0CH | +0 |
| LDX nn,Y       |   y    | ditto                  | +10H | +0 |
|                |    I   |Implicit                |      |    |
| a              |     R  |Relative(PC=PC+1+offset)|      | +2 |
| [nn,X]         |      x |Indexed indirect (X)    | -0CH | +2 |
| [nn],Y         |      y |Indirect indexed (Y)    | +04H | +1 |
| [nn]           |       @|Absolute indirect       | +20H | +2 |
|-------------------------+------------------------------------|
|BYTE     n(,...)         |Byte(s) (8-bit)                     |
|BYTE     'string'(,...)  |Byte text string(s)                 |
|DIRECT                   |Zero page addressing mode           |
|EXTEND                   |Absolute addressing mode            |
|RMB      nn(,...)        |Reserve Memory Bytes                |
|WORD     nn(,...)        |Word(s) (16-bit)                    |
|-------------------------+------------------------------------|
| A                       |Accumulator (8-bit)                 |
| P                       |Status Register (8-bit)             |
| PC                      |Program Counter (16-bit)            |
| S                       |Stack Pointer (9-bit, MSB=1)        |
| X  Y                    |Index Registers X and Y (8-bit)     |
|-------------------------+------------------------------------|
| a                       |Relative Address (-128 to +127)     |
| d                       |Destination                         |
| n                       |8-bit expression (0 to 255)         |
| nn                      |16-bit expression (0 to 65535)      |
| s                       |Source                              |
| string                  |String of ASCII characters          |
|-------------------------+------------------------------------|
| +                       |Arithmetic addition                 |
| -                       |Arithmetic subtraction              |
| *                       |Arithmetic multiplication           |
| /                       |Arithmetic division                 |
| &                       |Logical AND                         |
| ~                       |Logical NOT                         |
| v                       |Logical inclusive OR                |
| x                       |Logical exclusive OR                |
| <-                      |Rotate left                         |
| ->                      |Rotate right                        |
| [ ]                     |Indirect addressing                 |
| [ ]+                    |Indirect addressing, auto-increment |
| -[ ]                    |Auto-decrement, indirect addressing |
| { }                     |Combination of operands             |
| $                       |Program counter content             |
| %                       |~s = ~s+1 if crossing page boundary |
| !                       |PC = effective address of source    |
|-------------------------+------------------------------------|
|0000H to 00FFH           |Page 0 (see zero page addressing)   |
|0100H to 01FFH           |Page 1 (stack area, 01FFH = start)  |
|XX00H to XXFFH           |Page n (where n=XXH)                |
|FFFAH to FFFBH           |Non maskable interrupt (NMI) vector |
|FFFCH to FFFDH           |Reset (RES) vector                  |
|FFFEH to FFFFH           |Interrupt Request (IRQ) vector      |
|FFFEH to FFFFH           |Break command vector (see BRK)      |
|-------------------------+------------------------------------|
| 6501/6502               |16 address lines, 65536 bytes max.  |
| 6503/6505               |13 address lines, 8192 bytes max.   |
| 6504                    |12 address lines, 4096 bytes max.   |
----------------------------------------------------------------
}