Zilog EZ80F916 - Manual (Page 301)

eZ80
®
CPU
User Manual
UM007715-0415 CPU Instruction Set
292
RET
Return from Subroutine
Operation
PC  (SP)
Description
The RET instruction returns program control back to the point in the user’s application
code that had reached the current subroutine via a CALL instruction. The return address
pops from the stack and is written to the Program Counter. The MADL control bit must be
set to 1 to enable mixed-ADL mode code and interrupts. If the MADL is reset to 0, the suf-
fixed instructions do not operate correctly. More detailed operation is provided in
Table 83 .
Table 83. RET Instruction Detail
ADL Suffix Operation
0 None The starting Program Counter is {MBASE, PC[15:0]}.
Pop a 2-byte return address from {MBASE, SPS} into
PC[15:0]. The ADL mode bit remains cleared to 0. The
ending Program Counter is {MBASE, PC[15:0]}.
1 None The starting Program Counter is PC[23:0]. Pop a 3-byte
return address from SPL into PC[23:0]. The ADL mode
bit remains set to 1. The ending Program Counter is
PC[23:0].
0 .S An invalid suffix. RET.L must be used in all mixed-
memory mode applications.
1 .S An invalid suffix. RET.L must be used in all mixed-
memory mode applications.