Zilog Z8F0130 - Manual (Page 236)

eZ8
™
CPU Core
User Manual
UM012820-0810 SBCX Instruction
221
Attributes
Escaped Mode Addressing
Using Escaped Mode Addressing, address mode ER for the source or des-
tination specifies a working register with 4-bit addressing.
If the high byte of the source or destination address is EEh ( 11101110b ),
a working register is inferred. For example, the operand EE3h selects
Working Register R3. The full 12-bit address is provided by {RP[3:0],
RP[7:4], 3h} .
To access registers on Page Eh (addresses E00h to EFFh ), set the Page
Pointer, RP[3:0], to Eh and set the Working Group Pointer, RP[7:4] , to
the preferred Working Group.
Sample Usage
If Register 346h contains the value 2Eh , the Carry flag is set, and Regis-
ter 129h contains the value 1bh , the following statement leaves the value
12h in Register 346h , sets the D flag, and clears the C, Z, S, V, and H
flags:
SBCX 346h, 129h

Object Code: 38 12 93 46
If Register C6Ch contains the value 2Ah and the Carry flag is not set, the
following statement leaves the value 27h in Register C6Ch , sets the. D
flag, and clears the C, Z, S, V, and H flags:
SBCX C6Ch, #03h

Object Code: 39 03 0C 6C
Mnemonic
Destination,
Source Op Code
(Hex)
Operand 1 Operand 2 Operand 3
SBCX ER1, ER2 38 ER2[11:4] {ER2[3:0],
ER1[11:8]} ER1[7:0]
SBCX ER1, IM 39 IM {0h,
ER1[11:8]} ER1[7:0]