1. Tell me what is the difference between microprocessor and microcontroller?
Microprocessor is managers of the resources (I/O, memory) which lie outside of its architecture
Microcontroller have I/O, memory, etc. built into it and specifically designed for control
2. Do you know what is lst file?
☛ This file is also called as list file.
☛ It lists the opcodes ,addresses and errors detected by the assembler.
☛ List file is produced only when indicated by the user.
☛ It can be accessed by an editor and displayedon monitor screen or printed.
☛ Progammer uses this file to find the syntax errors and later fix them.
3. Explain me what are the commonly found errors in Embedded Systems?
☛ Damage of memory devices due to transient current and static discharges.
☛ Malfunctioning of address lines due to a short in the circuit.
☛ Malfunctioning of Data lines.
☛ Some memory locations being inaccessible in storage due to garbage or errors.
☛ Improper insertion of Memory devices into the memory slots.
☛ Faulty control signals.
4. What is interrupt latency? How can you reduce it?
Interrupt latency is a time taken to return from the interrupt service routine post handling a specific interrupt. By writing minor ISR routines, interrupt latency can be reduced.
5. Explain which 2 ports combine to form the 16 bit address for external memory access?
☛ Port0 and port2 together form the 16 bit address for external memory.
☛ Port0 uses pins 32 to 39 of 8051 to give the lower address bits(AD0-AD7)
☛ Port2 uses pins 21 to 28 of 8051 to give the higher address bits(A8-A15)
☛ This 16 bit address is used to access external memory if attached.
☛ When connected to external memory they cannot be used as input output ports.
6. Tell me are all the bits of flag register used in 8051?
☛ The flag register also called as the program status word uses only 6 bits.
☛ The two unused bits are user defineable flags.
☛ Carry, auxillary carry, parity and overflow flags are the conditional flags used in it.
☛ PSW.1 is a user definable bit and PSW.5 can be used as general purpose bit.
☛ Rest all flags indicate some or the other condition of an arithmetic operation.
7. Explain me which 8051 version uses Flash ROM?
☛ Atmel Corporation is manufacturing flash ROM
☛ At 89C51 chip of atmel is using flash ROM.
☛ Here no Rom eraser is needed.
☛ Erasing process is done by the PROM burner itself.
☛ To avoid use of PROM burner the 8052 version support in-system programming.
8. Tell me why is Model transformations used in the embedded system?
Model transformations involve multiple models that are used to define different views of a system. It provides different level of granularity that it doesn't use either the top-down approach or the bottom-up approach to implement the basic functionality of the system. It is used to integrate the library components used that involves the iteration of the model that needs to be constructed. It also involves the analysis of the model so that the process can be made automated by using the construction tools. The compilation made the progress by improving the code that is written in high level language and the code generator produce the code that is required for the machine language.
9. What are buses used for communication in embedded system?
For embedded system, the buses used for communication includes
I2C: It is used for communication between multiple ICs
CAN: It is used in automobiles with centrally controlled network
USB: It is used for communication between CPU and devices like mouse, etc.
While ISA, EISA, PCI are standard buses for parallel communication used in PCs, computer network devices, etc.
10. Explain me what are real-time embedded systems?
Real-time embedded systems are computer systems that monitor, respond or control an external environment. This environment is connected to the computer system through actuators, sensors, and other input-output interfaces.
