AT89LP428 Atmel Corporation, AT89LP428 Datasheet - Page 107

• Manufacturer Part Number: AT89LP428
• Manufacturer: Atmel Corporation

Specifications of AT89LP428

• Flash (kbytes): 4 Kbytes
• Max. Operating Frequency: 25 MHz
• Cpu: 8051-1C
• Max I/o Pins: 30
• Spi: 1
• Uart: 1
• Sram (kbytes): 0.75
• Eeprom (bytes): 512
• Self Program Memory: IAP
• Operating Voltage (vcc): 2.4 to 5.5
• Timers: 3
• Isp: SPI/OCD
• Watchdog: Yes

20. Instruction Set Summary
3654A–MICRO–8/09
The AT89LP428/828 is fully binary compatible with the MCS-51 instruction set. The difference
between the AT89LP428/828 and the standard 8051 is the number of cycles required to execute
an instruction. Instructions in the AT89LP428/828 may take 1, 2, 3, 4 or 5 clock cycles to com-
plete. The execution times of most instructions may be computed using
Table 20-1.
Generic Instruction Types
Most arithmetic, logical, bit and transfer instructions
Branches and Calls
Single Byte Indirect (i.e. ADD A, @Ri, etc.)
RET, RETI
MOVC
MOVX
MUL
DIV
INC DPTR
Arithmetic
ADD A, Rn
ADD A, direct
ADD A, @Ri
ADD A, #data
ADDC A, Rn
ADDC A, direct
ADDC A, @Ri
ADDC A, #data
SUBB A, Rn
SUBB A, direct
SUBB A, @Ri
SUBB A, #data
INC Rn
INC direct
INC @Ri
INC A
DEC Rn
DEC direct
DEC @Ri
DEC A
INC DPTR
INC /DPTR
(1)
Instruction Execution Times and Exceptions
Bytes
1
2
1
2
1
2
1
2
1
2
1
2
1
2
1
2
1
2
1
2
1
2
8051
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
24
–
Clock Cycles
AT89LP428/828
AT89LP
Cycle Count Formula
1
2
2
2
1
2
2
2
1
2
2
2
1
2
2
2
1
2
2
2
2
3
Table 20-1 on page
# bytes + 1
# bytes
2/4
2
4
3
2
4
2
(2)
Hex Code
28 - 2F
38 - 3F
98 - 9F
08 - 0F
18 - 1F
26 - 27
36 - 37
96 - 97
06 - 07
16 - 17
A5 A3
25
24
35
34
95
94
05
04
15
14
A3
107.
107