part-03. ALU+Registers+DATA-Memory
Posted: Tue May 26, 2015 11:41 am
Hi everyone,
In this topic, I will expand the former topics with DATA-Memory.
Because I've used a 16-bits Address-Bus, you can apply 64 K Memory.
I've divided Memory in 16 "cards". Each card consists of 4K. and has
it's own start-address. For 4K Memory, you need 12 bits (b11-b0),
so the remaining bits (b15-b12) are used for selection of a card.
Each card has it's own address-register and a 12-bits Full-Adder.
With these components you can use two address-methods,
absolute- and indexed addressing.
Two examples are given in the attached file.
This is the last example, in which you have to manually execute
all the buttons. Next time I will present you the Control-Unit.
This unit will take care of most actions.
In the meantime you can (have to) use the buttons,
this will help you to understand the Control-Unit.
Hans Cadans
In this topic, I will expand the former topics with DATA-Memory.
Because I've used a 16-bits Address-Bus, you can apply 64 K Memory.
I've divided Memory in 16 "cards". Each card consists of 4K. and has
it's own start-address. For 4K Memory, you need 12 bits (b11-b0),
so the remaining bits (b15-b12) are used for selection of a card.
Each card has it's own address-register and a 12-bits Full-Adder.
With these components you can use two address-methods,
absolute- and indexed addressing.
Two examples are given in the attached file.
This is the last example, in which you have to manually execute
all the buttons. Next time I will present you the Control-Unit.
This unit will take care of most actions.
In the meantime you can (have to) use the buttons,
this will help you to understand the Control-Unit.
Hans Cadans