Zilog Z86193 - Manual (Page 208)

Z8
®
CPU
User Manual
UM001604-0108 Instruction Description
201
Load External Data Autoincrement
Syntax
LDEI dst, src
Instruction Format
Operation
dst
←
src
r
←
r + 1
rr
←
rr + 1
This instruction is used for block transfers of data between external data memory and the
Register File. The address of the external data memory location is specified by a Working
Register Pair, and the address of the Register File location is specified by a Working Reg-
ister. The contents of the source location are loaded into the destination location. Both
addresses in the Working Registers are then incremented automatically. The contents of
the source are not affected.
Example 1
If Working Register Pair R6 and R7 contains
404Ah
, external data memory location
404Ah
and
404Bh
contain
ABh
and
C3h
respectively, and Working Register R2 contains
22h
, the statement:
LDEI @R2, @RR6
Op Code: 83 26
loads the value
ABh
into Register
22h
. Working Register Pair RR6 is incremented to
404Bh
and Working Register R2 is incremented to
23h
. A second
Cycles
OPC
(Hex)
Address Mode
dst src
OPC dst src 18 83 Ir Irr
OPC src dst 18 93 Irr Ir
Flag Description
C Unaffected
Z Unaffected
S Unaffected
V Unaffected
D Unaffected
H Unaffected