Micronas SDA 6000, User Manual

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SDA 6000
PRELIMINARY DATA SHEET
Version 2.1
C16X Microcontroller
4 - 41 Micronas
PSW Reset Value: 0000
H
ALU Status (N, C, V, Z, E, MULIP)
The condition flags (N, C, V, Z, E) within the PSW indicate the ALU status after the last
recently performed ALU operation. They are set by most of the instructions due to
specific rules, which depend on the ALU or data movement operation performed by an
instruction.
After execution of an instruction which explicitly updates the PSW register, the condition
flags cannot be interpreted as described in the following, because any explicit write to
the PSW register supersedes the condition flag values, which are implicitly generated by
the CPU. Explicitly reading the PSW register provides a read value that represents the
state of the PSW register after execution of the immediately preceding instruction.
Note: After reset, all of the ALU status bits are cleared.
Bit Function
N Negative Result
Set, when the result of an ALU operation is negative.
C Carry Flag
Set, when the result of an ALU operation produces a carry bit.
V Overflow Result
Set, when the result of an ALU operation produces an overflow.
Z Zero Flag
Set, when the result of an ALU operation is zero.
E End of Table Flag
Set, when the source operand of an instruction is 8000
H
or 80
H
.
MULIP Multiplication/Division In Progress
‘0’: There is no multiplication/division in progress.
‘1’: A multiplication/division has been interrupted.
USR0 User General Purpose Flag
May be used by the application software.
HLDEN,
ILVL, IEN Interrupt and EBC Control Fields
Define the response to interrupt requests and enable external bus
arbitration.
5 4 3 2 1 0 11 10 9 8 7 6 15 14 13 12
rw rw rw rw rw rw rw rw rw
ILVL(3..0) IEN HLD
EN
- - - USR0 MUL
IP
E Z V C N
rw