The wait state, TWait, is a extra clock cycle added to the machine cycle to allow time for external hardware to respond. During this extra cycle, none of the address, data, or control pins change state. Wait state is entered if READY is false (LOW) on the rising edge of clock following ALE. READY is sampled each rising edge of clock thereafter and wait state will not be exited until READY is true (HIGH).
The only way to exit WAIT state on the 8085 is to assert READY. You could perform a reset, but the processor will still remain in TWAIT if READY is not true.
In the 8086 microprocessor, a wait state is generated when the processor needs to wait for an external device to complete an operation before proceeding. This typically occurs when the processor accesses slower external memory or peripherals. The wait state extends the duration of a machine cycle to allow the external device to catch up, ensuring data integrity and proper operation. The addition of wait states can impact the overall performance of the system by increasing the total execution time of instructions.
A wait state in computing refers to a condition where a microprocessor is held idle until it can proceed with the execution of the next instruction. This can occur due to various reasons, such as unavailability of data or resources needed to complete the current operation. Efficient management of wait states is crucial for optimizing processor performance.
tristates
A T state is one cycle of the system clock.
When a microprocessor interfaces with a peripheral or memory device, the normal timing can be adjusted by introducing wait states. Wait states are delays inserted into the processor's operation cycle to allow slower devices sufficient time to complete their tasks, ensuring data integrity and proper communication. This adjustment helps synchronize the microprocessor's speed with that of the peripheral or memory, preventing data loss or corruption.
latches remember the last state but buffers do not
It could be called either a buffer or a wait state.
During a wait state in the 8086 microprocessor, the buses are typically inactive, meaning that the data bus (D0-D15) and address bus (A0-A19) do not carry valid data or address information. Instead, the control signals may indicate that the processor is in a wait state, often due to a slower peripheral or memory device not being ready for data transfer. The processor halts its operations and waits until the required conditions are met before resuming normal function.
The term "N core" means that the microprocessor contains 2 or more independent CPUs instead of the single CPU in the "traditional" microprocessor. The more CPUs in the microprocessor, the more instructions it can execute per clock cycle, because the extra CPUs work in parallel and usually do not have to wait for each other.
How does a microprocessor decode?
An Interrupt Service Routine (ISR) is executed by a microprocessor when an interrupt signal is received, indicating that a specific event requires immediate attention. The microprocessor pauses its current execution, saves the state of the interrupted task, and transfers control to the ISR to handle the interrupt. Once the ISR has completed its task, the microprocessor restores the saved state and resumes execution of the interrupted task. This mechanism allows for efficient handling of asynchronous events in real-time systems.