Q. Write an 8085 program and draw a flowchart to Sum a series of 8-bit numbers.(8085 Microprocessor Program) Flowchart/Algorithm Program Address Mnemonics Operand Opcode Comments 2000 LXI H, 3000H 21 Load H-L pair with address 3000H. 2001 00 2002 30 2003 MOV C, M 4E Move the counter from memory to reg. C. 2004 MVI … Read more

In this article, we will discuss 8085 microprocessor pin configuration or Pin diagram of 8085 or external architecture of 8085 microprocessor. Figure 1 shows the pin diagram of the 8085 Microprocessor. It has 40 pins and uses +5V for power. It is an 8-bit microprocessor. It is an appended version of the 8080 microprocessor. It can run … Read more

As we know that the 8085 microprocessor is an 8-bit microprocessor. So, a total of 256 instruction codes can be generated using 8-bit combinations. But out of 256 instruction codes, only 246 instruction codes are defined by INTEL Corporation for 8085 microprocessor. Each defined instruction code performs a unique task. These instruction codes are called … Read more

The total memory location required to feed the instruction in memory is called as instruction word size. The memory location of 8085 microprocessor can accommodate 8-bits of data. To store 16-bits data, they are stored in two consecutive memory locations (i.e. 2 Bytes). According to the instruction word size in 8085 microprocessor, there are three types of … Read more

In this article, we will discuss addressing modes of 8085 microprocessor. To perform any operation, we have to give the corresponding instructions to the microprocessor. In each instruction, a programmer has to specify three things: 1. Operation to be performed. 2. Address of source of data. 3. Address of destination of the result. The method … Read more

1. CMP  R R ⇒ A, B, C, D, E, H, L, and M Instruction word size  ⇒   1 Byte Operation ⇒ When this instruction will execute the content of Register R will compare with the content of accumulator (A) and the status of flag affect accordingly to the result. Note: It is nothing but SUB R instruction and … Read more

These instructions execute on the basis of the content of accumulator. When these instructions execute, the content of accumulator will shift by 1 bit either left or right as per the instruction. 1. RLC  no operand Instruction word size  ⇒   1 Byte Operation ⇒ When this instruction will execute the content of accumulator will shift (or rotate) … Read more

1. INR  Rp Rp ⇒ BC ≡ B DE ≡ D HL ≡ H Instruction word size  ⇒   1 Byte Operation ⇒ When this instruction will execute the content of Register pair Rp will increase by 1 and the final result will store in the Register pair Rp. [Rp] ← [Rp] + 1LSB Addressing Mode ⇒ Register Addressing Mode   2. DCX  … Read more

Rp = Register pair 1. LXI   Rp, 16 Bit data Rp ⇒ BC ≡ B DE ≡ D HL ≡ H SP Instruction word size  ⇒   3 Byte Operation ⇒ When this instruction will execute the 16-bit data will store in register pair Rp. [Rp ] ← 16-bit data Addressing Mode ⇒ Immediate Addressing Mode For example: LXI  D  2059 H [D] = 20 … Read more

1. ANA  R R ⇒ A, B, C, D, E, H, L, and M Instruction word size  ⇒   1 Byte Operation ⇒ When this instruction will execute the content of Register R will get AND operation with the accumulator (A) content bit by bit and the final result will store in the accumulator [A]. Addressing Mode ⇒ If R ≠ … Read more