M166 Datasheet, PDF (71/127 Pages) Siemens Semiconductor Group – C16x Family of Siemens 16-Bit CMOS Single-Chip Microcontrollers

30Mar98@15:00h
C166 Family Instruction Set
Instruction Description
EXTS
Begin EXTended Segment Sequence
EXTS
Syntax
Operation
Description
Note
EXTS
op1, op2
(count) ← (op2) [1 ≤ op2 ≤ 4]
Disable interrupts and Class A traps
Data_Segment = (op1)
DO WHILE ((count) ≠ 0 AND Class_B_trap_condition ≠ TRUE)
Next Instruction
(count) ← (count) - 1
END WHILE
(count) = 0
Data_Page = (DPPx)
Enable interrupts and traps
Overrides the standard DPP addressing scheme of the long and indirect
addressing modes for a specified number of instructions. During their exe-
cution, both standard and PEC interrupts and class A hardware traps are
locked. The EXTS instruction becomes immediately active such that no
additional NOPs are required.
For any long (’mem’) or indirect ([...]) address in an EXTS instruction
sequence, the value of op1 determines the 8-bit segment (address bits
A23-A16) valid for the corresponding data access. The long or indirect
address itself represents the 16-bit segment offset (address bits A15-A0).
The value of op2 defines the length of the effected instruction sequence.
The EXTS instruction must be used carefully (see introductory note).
The EXTS instruction is not available in the SAB 8XC166(W) devices.
Condition Flags
E
Z
V
C
N
-
-
-
-
-
Addressing Modes
E Not affected.
Z Not affected.
V Not affected.
C Not affected.
N Not affected.
Mnemonic
EXTS
Rwm, #irang2
EXTS
#seg, #irang2
Format
DC :00##-m
D7 :00##-0 ss 00
Bytes
2
4
Semiconductor Group
71
Version 1.2, 12.97