1989_MELPS_7700_Software_Manual

JSR
Operation
If absolute addressing mode,
M(S) ~ PCH
S ~ S - 1
M(S) ~ PCl
S ~ S - 1
PCl ~ ADl
PCH ~ ADH
Jump to Subroutine
JSR
If absolute long addressing mode,
M(S) ~ PG
S ~ S - 1
M(S) ~ PCH
S ~ S - 1
M(S) ~ PCl
S ~ S - 1
PCl ~ ADl
PCH ~ ADH
PG ~ ADG
If absolute indexed X indirect addressing mode,
M(S) ~ PCH.
S ~ S - 1
M(S) ~ pel
S ~ S - 1
pel ~ (ADH, ADl + X)
pet{ ~ (ADH, ADl + X + 1)
(ADl, ADH and ADG specify the instruction's second, third and fourth bytes, respectively.)
Description
The contents of the program counter PC (or the program bank register PG and
the program counter PC if absolute long addressing mode) are first saved on the
stack, then a jump occurs to the address shown for each addressing mode.
Status flags
Not affected.
Addressing mode Syntax Machine code Bytes Cycles
Absolute JSR mmll 2016, II, mm 3 6
Absolute long JSRL hhmmll 2216, II, mm, hh 4 8
Absolute indexed X indirect JSR (mmll, X) FC1s, II, mm 3 8
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