[CO}Vectored interrupt

Question

1. In case of vectored interrupt ,the i/o device will send vector address and then using this vector address,the IVT is referred which gives ISR address and then ISR is executed.So,the address that the I/o supplies is not the ISR address but actually the address which has the address of ISR.

2.In case if non vectored,the CPU waits until the interrupting device/controller supplies the vector address and then same process happens as above.But then what will be difference here in as vector address will be supplied at last, may be later.?

3. When we say interrupting device supplies the branch information,then does that "branch information" means that it is referring to branch address to IVT?

4. The entries in IVT i.,e the interrupt service subroutine address is fixed in the IVT for both vector and non vector interrupt?Means the IVT always has fixed entries for ISR irrespective of vectored/non-vectored intrrupts?

Is my understanding correct? Please correct me if i am missing anything?

Answer 1

Point 1 is correct

Point 2 is Wrong, the same process does not happen, The processor does not refer IVT in this case

Point 3 is correct

Point 4 is Wrong, IVT is only for Vectored interrupts

Ref: https://gateoverflow.in/2590/gate1995_1-3

Comments

Can you give me some reference where i can read about non vectored interrupts functionality ?I am under impression that they also refer IVT.I am referring william stallings.can you suggest some good reads regarding this please?

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https://superuser.com/questions/414290/when-a-non-vectored-interrupt-occurs-does-the-processor-ever-look-up-the-vector

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From william stallings

INTERRUPT VECTOR TABLE Interrupt processing on the x86 uses the interrupt vector
table. Every type of interrupt is assigned a number, and this number is used to
index into the interrupt vector table.This table contains 256 32-bit interrupt vectors,
which is the address (segment and offset) of the interrupt service routine for that interrupt
number.

It says "Every type of interrupt". Doesnt this mean that it applies to both vector and non vector interrupt.

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Every type of interrupt means 'interrupts which occur due to different reasons"

See Page 486, Table 12.3 of that book

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Thanks but can you refer me some book to read about it.I am still doubtfull about non vector interrupt.:(

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so incase of non vectored it doesnt refer IVT and goes directly to ISR?

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In Intel 8086, there are only Vectored Interrupts. Refer A.K Ray's Book on Microprocessors for H/W description of Intel 8086.