Zilog Z8F0130 - Manual (Page 217)

eZ8
™
CPU Core
User Manual
UM012820-0810 PUSH Instruction
202
Escaped Mode Addressing
Using Escaped Mode Addressing, address modes R or IR can specify a
working register. If the source address is prefixed by
Eh ( 1110b ), a work-
ing register is inferred. For example, if Working Register R12 ( Ch ) is the
preferred source operand, use ECh as the source operand in the Op Code.
To access registers with addresses E0h to EFh , either set the Working
Group Pointer, RP[7:4] , to Eh or use indirect addressing.
Sample Usage
If the Stack Pointer contains the value D20h , the following statement
stores the contents of Register FCh in location D1Fh :
PUSH FCh

Object Code: 70 FC
After the PUSH operation, the Stack Pointer contains the value D1Fh .
If the Stack Pointer contains the value E61h and Working Register R4
contains FCh , the following statement stores the contents of Register FCh
in location E60h :
PUSH @R4

Object Code: 71 E4
After the PUSH operation, the Stack Pointer contains the value E60h .
If the Stack Pointer contains the value D20h , the following statement
stores the value FCh in location D1Fh :
PUSH #FCh

Object Code: 1F70FC
After the PUSH operation, the Stack Pointer contains the value D1Fh .