Zilog Z80380 - Manual (Page 52)

5-18
Z380 ™
U SER ' S M ANUAL
DC-8297-03
Z ILOG
5.6 NOTATION AND BINARY ENCODING (Continued)
Condition Codes. The following symbols describe the
condition codes.
Z Zero*
NZ Not Zero*
C Carry*
NC No Carry*
S Sign
NS No Sign
NV No Overflow
V Overflow
PE Parity Even
PO Parity Odd
P Positive
M Minus
*Abbreviated set
Field Encoding. For opcode binary format in the Tables,
use the following convention:
For example, to get the opcode format on the instruction
LD (IX+12h), C
First, find out the entry for “LD (XY+d),R”. That entry has
a opcode format of
11 y11 101 01 110 -r-
←
d
→
On the bottom of the each instruction, there are the field
encodings, if applicable. For the cases which call out “per
convention,” then use the following encoding:
r Reg
000 B
001 C
010 D
011 E
100 H
101 L
111 A
To form the opcode, first, look for the “y” field value for IX
register, which is 0.
Then find “r” field value for the C register, which is 001.
Replace “y” and “r” field with the value from the table,
replace “d” value with the real number. The results being:
76 543 210 HEX
11 011 101 DD
01 110 001 71
00 010 010 21
5.7 EXECUTION TIME
i in the execution time column indicates an I/O read
operation. The time required for a read operation is shown
in the Table 5-18 below.
o in the execution time column indicates an I/O write
operation. The time required for a write operation is shown
in the Table 5-18 below.
All entries in the table below assume no wait states. The
number of wait states per operation must be added to
these numbers.
Table 5-18 details the execution time for each instruction
encoding. All execution times are for instruction execution
only. Clock cycles required for fetch and decode are not
included because most of the time the clocks required for
these operations occur in parallel with execution of the
previous instruction(s).
r in the execution time column indicates a memory read
operation. The time required for a read operation is shown
in the Table 5-18 below.
w in the execution time column indicates a memory write
operation. The time required for a write operation is shown
in the Table 5-18 below.