Microprocessor of Embedded System
Microprocessors are the computational core of embedded systems, compact yet powerful units that execute real-time tasks in various applications. Integrated with a CPU, memory, and I/O interfaces, microprocessors enable efficient processing and control in devices like automotive systems, smart appliances, and IoT devices. Programming languages such as C and assembly are commonly used for software development, optimizing performance and power consumption. Microprocessors play a crucial role in shaping the functionality and reliability of embedded systems, driving innovation and advancements in embedded computing across industries, from healthcare and automotive to industrial automation and consumer electronics.
Z80 is mainly based on
Intel 8080.
Its architecture is based on Intel 8080 but has an extended instruction set and hardware improvement.
Flag register of Z80 is also known as
Program status word.
The flag register of Z80 contains status information such as carry, overflow, signed etc.
What are the two register sets used in Z80?
Main and alternate.
Z80 have two sets of registers which are the main registers and alternate registers.
How an alternate set of the register can be identified in Z80?
‘Suffix.
In order to identify the main register and alternate register ‘ is used in the suffix.
What is the purpose of memory refresh register of Z80?
To control on-chip DRAM.
In addition to the general purpose registers, a stack pointer, program counter, and two index registers are included in Z80. It was also used in many embedded designs because of its high-quality performance and for its in-built refresh circuitry for DRAMs.
What is the clock frequency of Z80?
4 MHz.
It is the maximum clock frequency or runs a time of the processor.
Which are the two additional registers of Z80?
Interrupt vector and memory refresh.
The Interrupt vector(IV) register is used in the interrupt handling. Mode 2 is used to point the required software routine to process the interrupt. In mode 1, the interrupt vector is supplied via the external data bus.
By which instruction does the switching of registers take place?
EXX instruction.
Only one set of registers can be used at one time and the switching of registers and data transfer is performed by the EXX instruction.
Which signal is used to differentiates the access from a normal memory cycle?
IORQ.
The IORQ signal is used to differentiate the access from a normal memory cycle. These input/output accesses are similar from a hardware perspective to a memory cycle but only occur when an input/output port instruction is executed.