The 8085 Microprocessor has Serial Input/Output lines consisting of two pins as follows:
1. Serial Output Data (SOD) 2. Serial Input Data (SID)
They both are specially made for Input/Output which is further controlled by software. The transfer of data is controlled with the help of two instructions, i.e, SIM and RIM.
Now, let’s see both the pins one-by-one:
- Serial Output Data (SOD):
The SIM Instruction should be initiated in order to output data in serial manner. This is done through the SOD Line.
MVI A, 80H : Set D7 in the accumulator=1
RAR : Set D6 = 1 and bring carry into D7
SIM : Output D7
In the above set of instructions, the serial output line is enabled by rotating 1 into bit position D6; the instruction SIM outputs the carry bit through bit position D7.
It can be represented as:
Figure – Interpretation by SIM Instruction
- Serial Input Data (SID):
In SID, the RIM Instruction is initiated to input data in a serial manner. This is done through SID line.
It can be represented as:
Figure – Interpretation by RIM Instruction
In a software controlled Input/Output system, the SID and SOD lines eliminate the need of an input and output port respectively.
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- Interrupts in 8085 microprocessor
- Registers of 8085 microprocessor
- Pin diagram of 8085 microprocessor
- Bus organization of 8085 microprocessor
- Branching instructions in 8085 microprocessor
- Arithmetic instructions in 8085 microprocessor
- Difference between SIM and RIM instructions in 8085 microprocessor
- Flag register in 8085 microprocessor
- Addressing modes in 8085 microprocessor
- Instruction cycle in 8085 microprocessor
- Interface 8254 PIT with 8085 microprocessor
- Differences between 8085 and 8086 microprocessor
- Difference between 8080 and 8085 Microprocessor
- Logical instructions in 8085 microprocessor
- Interface 8255 with 8085 microprocessor for addition
- Reset Accumulator (8085 & 8086 microprocessor)
- Data transfer instructions in 8085 microprocessor
- Interface 8255 with 8085 microprocessor for 1’s and 2’s complement of a number
- Subtract content of two ports by interfacing 8255 with 8085 microprocessor
- Difference between Serial Port and Parallel Ports
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