1989_MELPS_7700_Software_Manual

BPL
Branch on Result Plus
BPL
Operation
When N=O,
PC ~ PC + 2 ± REL (REL is instruction's second byte)
PG ~ PG + 1 (if carry on PC), PG ~ PG - 1 (if borrow on PC)
When N=1,
PC ~ PC + 2
PG ~ PG + 1 (if carry on PC)
Description
When the negative flag N is clear (0), the BPL instruction causes a branch to the
specified address. The branch address is specified by a relative address.
When the negative flag N is set (1), the program advances to next step without
any action.
Status flags
Not affected.
Addressing mode Syntax I Machine code I Bytes I Cycles I
Relative BPL rr .1101S, rr
(Note1) The cycles-count increases by 2 when a branch occurs.
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