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Opcode table
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<h2 id="table-values">Table values</h2> <p>The structure and arrangement of an opcode table appears as follows: </p> <table><tbody><tr><th></th><th scope="column">0</th><th>1</th><th>2</th><th>3</th><th>4</th><th>5</th><th>6</th><th>7</th><th>8</th><th>9</th><th>A</th><th>B</th><th>C</th><th>D</th><th>E</th><th>F</th></tr><tr><th scope="row">0</th><td>00</td><td>01</td><td>02</td><td>03</td><td>04</td><td>05</td><td>06</td><td>07</td><td>08</td><td>09</td><td>0A</td><td>0B</td><td>0C</td><td>0D</td><td>0E</td><td>0F</td></tr><tr><th scope="row">1</th><td>10</td><td>11</td><td>12</td><td>13</td><td>14</td><td>15</td><td>16</td><td>17</td><td>18</td><td>19</td><td>1A</td><td>1B</td><td>1C</td><td>1D</td><td>1E</td><td>1F</td></tr><tr><th scope="row">2</th><td>20</td><td>21</td><td>22</td><td>23</td><td>24</td><td>25</td><td>26</td><td>27</td><td>28</td><td>29</td><td>2A</td><td>2B</td><td>2C</td><td>2D</td><td>2E</td><td>2F</td></tr><tr><th scope="row">3</th><td>30</td><td>31</td><td>32</td><td>33</td><td>34</td><td>35</td><td>36</td><td>37</td><td>38</td><td>39</td><td>3A</td><td>3B</td><td>3C</td><td>3D</td><td>3E</td><td>3F</td></tr><tr><th scope="row">4</th><td>40</td><td>41</td><td>42</td><td>43</td><td>44</td><td>45</td><td>46</td><td>47</td><td>48</td><td>49</td><td>4A</td><td>4B</td><td>4C</td><td>4D</td><td>4E</td><td>4F</td></tr><tr><th scope="row">5</th><td>50</td><td>51</td><td>52</td><td>53</td><td>54</td><td>55</td><td>56</td><td>57</td><td>58</td><td>59</td><td>5A</td><td>5B</td><td>5C</td><td>5D</td><td>5E</td><td>5F</td></tr><tr><th scope="row">6</th><td>60</td><td>61</td><td>62</td><td>63</td><td>64</td><td>65</td><td>66</td><td>67</td><td>68</td><td>69</td><td>6A</td><td>6B</td><td>6C</td><td>6D</td><td>6E</td><td>6F</td></tr><tr><th scope="row">7</th><td>70</td><td>71</td><td>72</td><td>73</td><td>74</td><td>75</td><td>76</td><td>77</td><td>78</td><td>79</td><td>7A</td><td>7B</td><td>7C</td><td>7D</td><td>7E</td><td>7F</td></tr><tr><th scope="row">8</th><td>80</td><td>81</td><td>82</td><td>83</td><td>84</td><td>85</td><td>86</td><td>87</td><td>88</td><td>89</td><td>8A</td><td>8B</td><td>8C</td><td>8D</td><td>8E</td><td>8F</td></tr><tr><th scope="row">9</th><td>90</td><td>91</td><td>92</td><td>93</td><td>94</td><td>95</td><td>96</td><td>97</td><td>98</td><td>99</td><td>9A</td><td>9B</td><td>9C</td><td>9D</td><td>9E</td><td>9F</td></tr><tr><th scope="row">A</th><td>A0</td><td>A1</td><td>A2</td><td>A3</td><td>A4</td><td>A5</td><td>A6</td><td>A7</td><td>A8</td><td>A9</td><td>AA</td><td>AB</td><td>AC</td><td>AD</td><td>AE</td><td>AF</td></tr><tr><th scope="row">B</th><td>B0</td><td>B1</td><td>B2</td><td>B3</td><td>B4</td><td>B5</td><td>B6</td><td>B7</td><td>B8</td><td>B9</td><td>BA</td><td>BB</td><td>BC</td><td>BD</td><td>BE</td><td>BF</td></tr><tr><th scope="row">C</th><td>C0</td><td>C1</td><td>C2</td><td>C3</td><td>C4</td><td>C5</td><td>C6</td><td>C7</td><td>C8</td><td>C9</td><td>CA</td><td>CB</td><td>CC</td><td>CD</td><td>CE</td><td>CF</td></tr><tr><th scope="row">D</th><td>D0</td><td>D1</td><td>D2</td><td>D3</td><td>D4</td><td>D5</td><td>D6</td><td>D7</td><td>D8</td><td>D9</td><td>DA</td><td>DB</td><td>DC</td><td>DD</td><td>DE</td><td>DF</td></tr><tr><th scope="row">E</th><td>E0</td><td>E1</td><td>E2</td><td>E3</td><td>E4</td><td>E5</td><td>E6</td><td>E7</td><td>E8</td><td>E9</td><td>EA</td><td>EB</td><td>EC</td><td>ED</td><td>EE</td><td>EF</td></tr><tr><th scope="row">F</th><td>F0</td><td>F1</td><td>F2</td><td>F3</td><td>F4</td><td>F5</td><td>F6</td><td>F7</td><td>F8</td><td>F9</td><td>FA</td><td>FB</td><td>FC</td><td>FD</td><td>FE</td><td>FF</td></tr></tbody></table> <p>Each cell from 00-FF contains information about the operation such as the equivalent assembly instruction corresponding to the opcode, parameters, and CPU cycle counts. </p> <h2 id="example-opcode-table">Example opcode table</h2> <p>This is the opcode table for the <a href="/facts/MOS_Technology_6502/q9YLwkzm">MOS Technology 6502</a> microprocessor from 1975. The 6502 uses 8-bit opcodes. Of the 256 possible opcodes available using an 8-bit pattern, the original 6502 uses only 151 of them, organized into 56 instructions with (possibly) multiple <a href="/facts/Addressing_mode/g78wINgK">addressing modes</a>.<a class="footnote-ref" id="fnref:1" href="#fn:1"><sup>1</sup></a> Because not all the 256 opcodes are not used, some opcode spaces are blank and the low nibble columns 3, 7, B, and F are missing from the table. </p> <table><tbody><tr><th colspan="13">Opcode matrix for the 6502 instruction set</th></tr><tr><td colspan="13">Addressing modes: <i>A</i> – accumulator, <i>#</i> – immediate, <i>zpg</i> – zero page, <i>abs</i> – absolute, <i>ind</i> – indirect, <i>X</i> – indexed by X register, <i>Y</i> – indexed by Y register, <i>rel</i> – relative</td></tr><tr><th rowspan="2">High nibble</th><th colspan="12">Low nibble</th></tr><tr><th>0</th><th>1</th><th>2</th><th>4</th><th>5</th><th>6</th><th>8</th><th>9</th><th>A</th><th>C</th><th>D</th><th>E</th></tr><tr><th>0</th><td>BRK</td><td>ORA (<i>ind</i>,X)</td><td></td><td></td><td>ORA <i>zpg</i></td><td>ASL <i>zpg</i></td><td>PHP</td><td>ORA #</td><td>ASL A</td><td></td><td>ORA <i>abs</i></td><td>ASL <i>abs</i></td></tr><tr><th>1</th><td>BPL <i>rel</i></td><td>ORA (<i>ind</i>),Y</td><td></td><td></td><td>ORA <i>zpg</i>,X</td><td>ASL <i>zpg</i>,X</td><td>CLC</td><td>ORA <i>abs</i>,Y</td><td></td><td></td><td>ORA <i>abs</i>,X</td><td>ASL <i>abs</i>,X</td></tr><tr><th>2</th><td>JSR <i>abs</i></td><td>AND (<i>ind</i>,X)</td><td></td><td>BIT <i>zpg</i></td><td>AND <i>zpg</i></td><td>ROL <i>zpg</i></td><td>PLP</td><td>AND #</td><td>ROL A</td><td>BIT <i>abs</i></td><td>AND <i>abs</i></td><td>ROL <i>abs</i></td></tr><tr><th>3</th><td>BMI <i>rel</i></td><td>AND (<i>ind</i>),Y</td><td></td><td></td><td>AND <i>zpg</i>,X</td><td>ROL <i>zpg</i>,X</td><td>SEC</td><td>AND <i>abs</i>,Y</td><td></td><td></td><td>AND <i>abs</i>,X</td><td>ROL <i>abs</i>,X</td></tr><tr><th>4</th><td>RTI</td><td>EOR (<i>ind</i>,X)</td><td></td><td></td><td>EOR <i>zpg</i></td><td>LSR <i>zpg</i></td><td>PHA</td><td>EOR #</td><td>LSR A</td><td>JMP <i>abs</i></td><td>EOR <i>abs</i></td><td>LSR <i>abs</i></td></tr><tr><th>5</th><td>BVC <i>rel</i></td><td>EOR (<i>ind</i>),Y</td><td></td><td></td><td>EOR <i>zpg</i>,X</td><td>LSR <i>zpg</i>,X</td><td>CLI</td><td>EOR <i>abs</i>,Y</td><td></td><td></td><td>EOR <i>abs</i>,X</td><td>LSR <i>abs</i>,X</td></tr><tr><th>6</th><td>RTS</td><td>ADC (<i>ind</i>,X)</td><td></td><td></td><td>ADC <i>zpg</i></td><td>ROR <i>zpg</i></td><td>PLA</td><td>ADC #</td><td>ROR A</td><td>JMP (<i>ind</i>)</td><td>ADC <i>abs</i></td><td>ROR <i>abs</i></td></tr><tr><th>7</th><td>BVS <i>rel</i></td><td>ADC (<i>ind</i>),Y</td><td></td><td></td><td>ADC <i>zpg</i>,X</td><td>ROR <i>zpg</i>,X</td><td>SEI</td><td>ADC <i>abs</i>,Y</td><td></td><td></td><td>ADC <i>abs</i>,X</td><td>ROR <i>abs</i>,X</td></tr><tr><th>8</th><td></td><td>STA (<i>ind</i>,X)</td><td></td><td>STY <i>zpg</i></td><td>STA <i>zpg</i></td><td>STX <i>zpg</i></td><td>DEY</td><td></td><td>TXA</td><td>STY <i>abs</i></td><td>STA <i>abs</i></td><td>STX <i>abs</i></td></tr><tr><th>9</th><td>BCC <i>rel</i></td><td>STA (<i>ind</i>),Y</td><td></td><td>STY <i>zpg</i>,X</td><td>STA <i>zpg</i>,X</td><td>STX <i>zpg</i>,Y</td><td>TYA</td><td>STA <i>abs</i>,Y</td><td>TXS</td><td></td><td>STA <i>abs</i>,X</td><td></td></tr><tr><th>A</th><td>LDY #</td><td>LDA (<i>ind</i>,X)</td><td>LDX #</td><td>LDY <i>zpg</i></td><td>LDA <i>zpg</i></td><td>LDX <i>zpg</i></td><td>TAY</td><td>LDA #</td><td>TAX</td><td>LDY <i>abs</i></td><td>LDA <i>abs</i></td><td>LDX <i>abs</i></td></tr><tr><th>B</th><td>BCS <i>rel</i></td><td>LDA (<i>ind</i>),Y</td><td></td><td>LDY <i>zpg</i>,X</td><td>LDA <i>zpg</i>,X</td><td>LDX <i>zpg</i>,Y</td><td>CLV</td><td>LDA <i>abs</i>,Y</td><td>TSX</td><td>LDY <i>abs</i>,X</td><td>LDA <i>abs</i>,X</td><td>LDX <i>abs</i>,Y</td></tr><tr><th>C</th><td>CPY #</td><td>CMP (<i>ind</i>,X)</td><td></td><td>CPY <i>zpg</i></td><td>CMP <i>zpg</i></td><td>DEC <i>zpg</i></td><td>INY</td><td>CMP #</td><td>DEX</td><td>CPY <i>abs</i></td><td>CMP <i>abs</i></td><td>DEC <i>abs</i></td></tr><tr><th>D</th><td>BNE <i>rel</i></td><td>CMP (<i>ind</i>),Y</td><td></td><td></td><td>CMP <i>zpg</i>,X</td><td>DEC <i>zpg</i>,X</td><td>CLD</td><td>CMP <i>abs</i>,Y</td><td></td><td></td><td>CMP <i>abs</i>,X</td><td>DEC <i>abs</i>,X</td></tr><tr><th>E</th><td>CPX #</td><td>SBC (<i>ind</i>,X)</td><td></td><td>CPX <i>zpg</i></td><td>SBC <i>zpg</i></td><td>INC <i>zpg</i></td><td>INX</td><td>SBC #</td><td>NOP</td><td>CPX <i>abs</i></td><td>SBC <i>abs</i></td><td>INC <i>abs</i></td></tr><tr><th>F</th><td>BEQ <i>rel</i></td><td>SBC (<i>ind</i>),Y</td><td></td><td></td><td>SBC <i>zpg</i>,X</td><td>INC <i>zpg</i>,X</td><td>SED</td><td>SBC <i>abs</i>,Y</td><td></td><td></td><td>SBC <i>abs</i>,X</td><td>INC <i>abs</i>,X</td></tr></tbody></table> <h2 id="external-links">External links</h2> <ul><li><a href="http://www.pastraiser.com/cpu/gameboy/gameboy_opcodes.html">Game Boy LR35902 opcode table</a></li> <li><a href="http://clrhome.org/table/">Z80 opcode table</a></li> <li><a href="http://www.sparksandflames.com/files/x86InstructionChart.html">Intel x86 opcode table</a></li> <li><a href="http://www.oxyron.de/html/opcodes02.html">6502/6510/8500/8502 opcode table</a></li></ul> <h2 id="references">References</h2> <ol> <li id="fn:1"><p>Parker, Neil. "The 6502/65C02/65C816 Instruction Set Decoded". Neil Parker's Apple II page. Archived from the original on 2019-07-16. Retrieved 2019-07-16. <a href="http://nparker.llx.com/a2/opcodes.html" target="_blank">http://nparker.llx.com/a2/opcodes.html</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> </ol>