27. Conditional branch

27.1. Name

Bcc -- Conditional branch

27.2. Synopsis

        Bcc        <label>

        Size = (Byte, Word, Long*)

        * 68020+ only

27.3. Function

If condition true then program execution continues at: (PC) + offset. PC value is instruction address more two. Offset is the relative value in bytes which separate Bcc instruction of mentioned label. Condition code 'cc' specifies one of the following, where 'bitmap' is the value in bits 8-11 of the instruction word :

BitmapCCNameFlagsBitmapCCNameFlags
0000FFalseZ = 11000VCoVerflow ClearV = 0
0001TTrueZ = 01001VSoVerflow SetV = 1
0010HIHIghC + Z = 01010PLPLusN = 0
0011LSLow or SameC + Z = 11011MIMInusN = 1
0100CCCarry ClearC = 01100GEGreater or EqualN (+) V = 0
0101CSCarry SetC = 11101LTLess ThanN (+) V = 1
0110NENot EqualZ = 01110GTGreater ThanZ + (N (+) V) = 0
0111EQEQualZ = 11111LELess or EqualZ + (N (+) V) = 1

27.4. Format

        -----------------------------------------------------------------
        |15 |14 |13 |12 |11 |10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
        |---|---|---|---|---------------|-------------------------------|
        | 0 | 1 | 1 | 0 |   CONDITION   |         8 BITS OFFSET         |
        |---------------------------------------------------------------|
        |            16 BITS OFFSET, IF 8 BITS OFFSET = $00             |
        |---------------------------------------------------------------|
        |            32 BITS OFFSET, IF 8 BITS OFFSET = $FF             |
        -----------------------------------------------------------------

27.5. Result

        None.

27.6. See also

BRA DBcc Scc