Zilog EZ80F916 - Manual (Page 400)

eZ80
®
CPU
User Manual
UM007715-0415 Glossary
391
register can be read from and written to using the dedicated instructions LD A,R and LD R,A,
respectively.
REQ.
Request.
RES.
Reset Bit; a bit manipulation instruction.
RET.
Return from subroutine; a program control instruction.
RET cc.
Conditional Return; a program control instruction.
RETI.
Return from Interrupt; a program control instruction.
RETN.
Return from nonmaskable interrupt; a program control instruction.
RL.
ROMless Control. Rotate Left; a rotate instruction.
RLA.
Rotate Left–Accumulator; a rotate instruction.
RLC.
Rotate Left Circular; a rotate instruction.
RLCA.
Rotate Left Circular–Accumulator; a rotate instruction.
RLD.
Rotate Left Decimal; a rotate instruction.
ROM.
See Read-Only Memory.
ROMCS.
ROM Chip Select.
ROMless.
No Read-Only Memory. External memory is required.
RP.
Register Pointer.
RR.
Read Register. Rotate Right; a rotate instruction.
RRA.
Rotate Right–Accumulator; a shift instruction.
RRC.
Rotate Right Circular; a shift instruction.
RRCA.
Rotate Right Circular–Accumulator; a shift instruction.
RRD.
Rotate Right Decimal; a shift instruction.
RSMIX.
Reset MIXED MEMORY Mode Flag; a processor control instruction.
RST.
Restart; a program control instruction. as opposed to RES or RESET.
S.
See Sign Flag.
SBC.
Subtract with Carry; an arithmetic instruction.
SCF.
Set Carry Flag; a processor control instruction.
SCLK.
System Clock.
SET.
Set Bit; a bit manipulation instruction.
SIEF.
Set IE Flag.
Sign Flag.
The Sign flag stores the state of the most significant bit of the accumulator (bit 7). Single-instruc-
tion mode. One of two types of mode changes available to the eZ80 ® . Single-instruction mode changes
allow certain instructions to operate using either ADL or Z80 addressing mode without making a persistent
change to either mode. See persistent mode.
SLA.
Shift Left; a shift instruction.
SLL.
Shift Left Logical.