AT89LP51ED2-20JU Atmel, AT89LP51ED2-20JU Datasheet - Page 183

• Manufacturer Part Number: AT89LP51ED2-20JU
• Description: 8-bit Microcontrollers - MCU 64KB 20MHz 2.4V-5.5V
• Manufacturer: Atmel

Specifications of AT89LP51ED2-20JU

• Rohs: yes
• Core: 8051
• Processor Series: AT89x
• Data Bus Width: 8 bit
• Maximum Clock Frequency: 20 MHz
• Program Memory Size: 64 KB
• Data Ram Size: 256 B
• On-chip Adc: Yes
• Operating Supply Voltage: 2.4 V to 5.5 V
• Operating Temperature Range: - 40 C to + 85 C
• Package / Case: PLCC-44
• Mounting Style: SMD/SMT
• Data Rom Size: 4 KB
• Interface Type: 2-Wire, SPI, UART
• Number Of Programmable I/os: 36
• Number Of Timers: 3
• Program Memory Type: Flash
• Factory Pack Quantity: 27

22.1.9
22.1.10
3714A–MICRO–7/11
Description: MAC AB multiplies the signed 16-bit integers in the register pairs {AX, A} and {BX, B} and adds the 32-bit product
Description: MOV /DPTR, #data16 loads the unselected Data Pointer with the 16-bit constant indicated. The third byte is the
Operation: MAC
Operation: MOV
Encoding:
Encoding:
Function: Multiply and Accumulate
Function: Load Alternate Data Pointer with a 16-bit constant
MAC AB
MOV /DPTR, #data16
Example: Originally the Accumulator holds the value 80 (50H). Register B holds the value 160 (0A0H). The instruction,
Example: When DPS = 0, the instruction sequence,
Cycles: 9
Cycles: 3
Bytes: 2
Bytes: 2
to the 40-bit M register. The low-order bytes of the 16-bit operands are stored in A and B, and the high-order
bytes in AX and BX respectively. The four operand registers are unaffected by the operation. If the addition of the
product to the accumulated sum in M results in a two's complement overflow, the overflow flag is set; otherwise it
is not cleared. The carry flag is set if the result is negative and cleared if positive.
MAC AB
will give the product 12, 800 (3200H), so B is changed to 32H (00110010B) and the Accumulator is cleared. The
overflow flag is set, carry is cleared.
(M
high-order byte, while the fourth byte holds the lower-order byte. No flags are affected.
MOV
MOV /DPTR, # 5678H
loads the value 1234H into the first Data Pointer: DPH0 holds 12H and DPL0 holds 34H; and loads the value
5678H into the second Data Pointer: DPH1 hold 56H and DPL1 holds 78H.
IF (DPS) = 0
THEN
ELSE
39-0
A5
A5
(DP1H) ← #data
(DP1L) ← #data
(DP0H) ← #data
(DP0L) ← #data
) ← (M) + { (AX), (A) } X { (BX), (B) }
DPTR, # 1234H
1
7-0
7-0
15-8
15-8
90
0
1
AT89LP51RD2/ED2/ID2 Preliminary
0
immed. data 15-8
0
1
0
0
immed. data 7-0
183