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59 lines
1.7 KiB
Plaintext
59 lines
1.7 KiB
Plaintext
{{DISPLAYTITLE:_READBIT}}
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The [[_READBIT]] function is used to check the state of a specified bit of a integer value.
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{{PageSyntax}}
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:{{Parameter|result}} = [[_READBIT]]({{Parameter|numericalVariable}}, {{Parameter|numericalValue}})
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{{Parameters}}
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* {{Parameter|numericalVariable}} is the variable to read the state of a bit of and can be of the following types: [[_BYTE]], [[INTEGER]], [[LONG]], or [[_INTEGER64]].
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* Integer values can be signed or [[_UNSIGNED]].
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* {{Parameter|numericalValue}} the number of the bit to be read.
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{{PageDescription}}
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* Used to check the current state of a bit in an integer value.
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* Returns -1 if the bit is set(1), otherwise returns 0 if the bit is not set(0)
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* Bits start at 0 (so a [[_BYTE]] has bits 0 to 7, [[INTEGER]] 0 to 15, and so on)
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==Availability==
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* '''Version 1.4 and up'''.
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{{PageExamples}}
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''Example 1:''
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{{CodeStart}}
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A~%% = {{Cl|_SETBIT}}(A~%%,4)
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{{Cl|PRINT}} "Bit 4 is currently ";
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IF {{Cl|_READBIT}}(A~%%,4) = -1 THEN {{Cl|PRINT}} "ON" ELSE {{Cl|PRINT}} "OFF"
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{{Cl|PRINT}} "And bit 2 is currently ";
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IF {{Cl|_READBIT}}(A~%%,2) = -1 THEN {{Cl|PRINT}} "ON" ELSE {{Cl|PRINT}} "OFF"
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{{CodeEnd}}
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{{OutputStart}}
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Bit 4 is currently ON
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And bit 2 is currently OFF
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{{OutputEnd}}
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''Example 2:''
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{{CodeStart}}
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B& = 12589575
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{{Cl|PRINT}} "B& ="; B&
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FOR I%% = 31 TO 0 STEP -1 '32 bits for a {{Cl|LONG}} value
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Binary$ = Binary$ + {{Cl|LTRIM$}}({{Cl|STR$}}({{Cl|ABS}}({{Cl|_READBIT}}(B&, I%%))))
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NEXT I%%
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{{Cl|PRINT}} "B& in binary is: "; Binary${{CodeEnd}}
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{{OutputStart}}
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B& = 12589575
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B& in binary is: 00000000110000000001101000000111
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{{OutputEnd}}
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{{PageSeeAlso}}
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* [[_SHL]], [[_SHR]], [[INTEGER]], [[LONG]]
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* [[_SETBIT]], [[_BYTE]], [[_INTEGER64]]
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* [[_RESETBIT]], [[_TOGGLEBIT]]
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{{PageNavigation}}
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