W77E058A40DL Datasheet, PDF (29/87 Pages) Nuvotem Talema – GENERAL DESCRIPTION

W77E058A
8. INSTRUCTION
The W77E058 executes all the instructions of the standard 8032 family. The operation of these
instructions, their effect on the flag bits and the status bits is exactly the same. However, timing of
these instructions is different. The reason for this is two fold. Firstly, in the W77E058, each machine
cycle consists of 4 clock periods, while in the standard 8032 it consists of 12 clock periods. Also, in the
W77E058 there is only one fetch per machine cycle i.e. 4 clocks per fetch, while in the standard 8032
there can be two fetches per machine cycle, which works out to 6 clocks per fetch.
The advantage the W77E058 has is that since there is only one fetch per machine cycle, the number
of machine cycles in most cases is equal to the number of operands that the instruction has. In case of
jumps and calls there will be an additional cycle that will be needed to calculate the new address. But
overall the W77E058 reduces the number of dummy fetches and wasted cycles, thereby improving
efficiency as compared to the standard 8032.
Table 2. Instructions that affect Flag settings
INSTRUCTION
ADD
ADDC
SUBB
MUL
DIV
DA A
RRC A
RLC A
SETB C
CARRY
X
X
X
0
0
X
X
X
1
OVERFLOW
AUXILIARY
CARRY
X
X
X
X
X
X
X
X
INSTRUCTION
CLR C
CPL C
ANL C, bit
ANL C, bit
ORL C, bit
ORL C, bit
MOV C, bit
CJNE
CARRY
0
X
X
X
X
X
X
X
A "X" indicates that the modification is as per the result of instruction.
OVERFLOW
AUXILIARY
CARRY
Table 3. Instruction Timing for W77E058
INSTRUCTION
NOP
ADD A, R0
ADD A, R1
ADD A, R2
ADD A, R3
ADD A, R4
ADD A, R5
ADD A, R6
ADD A, R7
ADD A, @R0
ADD A, @R1
ADD A, direct
ADD A, #data
HEX
OP-CODE
00
28
29
2A
2B
2C
2D
2E
2F
26
27
25
24
BYTES
1
1
1
1
1
1
1
1
1
1
1
2
2
W77E058
MACHINE
CYCLES
1
1
1
1
1
1
1
1
1
1
1
2
2
W77E058
CLOCK
CYCLES
4
4
4
4
4
4
4
4
4
4
4
8
8
8032
CLOCK
CYCLES
12
12
12
12
12
12
12
12
12
12
12
12
12
W77E058 VS.
8032 SPEED
RATIO
3
3
3
3
3
3
3
3
3
3
3
1.5
1.5
- 29 -
Publication Release Date: April 17, 2007
Revision A10