Device access

iTS not difficulty. you can use 3-8 decoder to complete the job.

because you have only 5 device to access in fact. so you remain 3 no use.

I need clarification.

I have 1mb of microprocessor memory

Do you mean that your microprocessor (μP) has an internal memory of 1Mb or do you mean that your μP can access 1Mb of memory? In any case, I need to know how many addresses your μP can access.

6 devices of which 2 are 512kb and another is 1mb

There's something missing here. You have two 512kb devices and one 1Mb device. That's three devices, so how did it become 6 devices?

I need answers to these because, if your μP can access 1Mb of data, your memory (2-512kb and 1-1Mb) equals 2Mb means that you have more memory than your μP can handle.

Yes,I do mean that the microprocessor has 1mb of internal memory.And regarding 6 devices,I have only mentioned 3 here because the remaining 3 are comparitively smaller in size and can be easily mapped onto the microprocessor's internal memory.So my question is how do I design my address decoding scheme to access these devices?

You still haven't completely answered my questions.

Okay, your μP has 1Mb of internal memory. How much memory can it access both internally and externally? If your μP can access a total of 2Mb, and you have 1Mb of internal memory, then that means you can add 1Mb of external memory.

Perhaps it might be easier if you tell me how many address lines you have.

I hate to be so negative, but as you do not seem to understand what you need to supply as information for anyone here to help you, means to me that you are not in a position to follow the needed technical information that will be given to you by the CR4 people.....

The amount of memory your computer has, does not in fact directly (unless you are going to open up your computer and start attaching wires to the memory bus connections! which will stop it working completely as they are very sensitive to length of wire etc.) change on how you are connecting to these other devices.....usually.

I guess you have some memory chips and you want to expand the memory of your computer (PC?), please let us know....

Firstly you will need to tell us what your chips are, some are already in 8 bit format, some in 9 and some in single bit format (you will need at least 8 of these!). I have put this very simply, as there are many sorts of memory both in architecture and in speed......and and and.....

Waiting on your reply.

I am thinking of devices which are "Input/Output". with their own memory. You have 1 MB of memory with which to run your own processor. If I can go back to old Intel concepts, they have an IO bus... meaning that if you want to communicate with an external device, you hit the IO rather than memory... of course your peripheral might need some intelligence too. I don't see how you can do a memory map to include 5 quarts of water into a gallon can.