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what do you call a CPU less computer

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neptune

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i studied in computer architecture that we can build a computer without the use of CPU.

using only memory and its addressing, what is the name of that kind of computer ?
 
If my computer had no CPU I'd call it 'junk' :D.
 
A state machine.

Agreed. I made a simple circuit to switch lights on and off in my house in the 1980's. It consisted of a 1 sec clock via a binary counter derived from a crystal with a CD4060 divider clocking the address pins of a preprogrammed EPROM. The data lines at any address/time drove lines via a buffer to switch a relay. Once synched at midnight on a specific day ran for years without issues. A switch behind the door drove CE high thus disabling the whole system when I arrived home from work.

A state machine/computer without a CPU.
 
A state machine is very limited as to the functions it can perform as compared to a von Neumann computer.
 
An analog computer, to my knowledge, does not use a CPU. E
True, but it also doesn't use memory, as the OP stated in his question, which implies a digital machine. ;)
 
True, but it also doesn't use memory, as the OP stated in his question, which implies a digital machine. ;)

Slight OT from the OP's original query, but it does, but not as you know as memory in a digital world. An integrator/differentiator circuit often used in analog computers relies on its current state depending on its previous state. i.e. Intergrating f(n) with give you a +constant. This constant is historic and will be involved in the next integrate. Often appearing as a drift in an output in a simple circuit intergrator circuit.

Have a Google at "Heavyside Step Functions" if you have eaten and are in the mood.
 
if we want to perform 2+2 then we can give it to adder or we can give it to memory
2+2 will form address to the memory location containing answer 4.
similarly we can perform write function, to write anything in that same memory.
is this still a state machine ?
 
if we want to perform 2+2 then we can give it to adder or we can give it to memory
2+2 will form address to the memory location containing answer 4.
similarly we can perform write function, to write anything in that same memory.
is this still a state machine ?

I don't believe that is a state machine, because the next state is non dependent on the current state, but only on the external inputs (addresses). I would call your machine a look-up table that mimics addition by copying data derived from data calculated by other means, a priori. A state machine implementation would be more like loading two down-counters with the two numbers to be summed then counting the total number of pulses required to bring both counters to a zero count using a third counter.
 
thanx for reply ..
can this lookup table compute any function..if it can write and read in itself
 
well i looked up on net on look up table, but i am sure that was not the name of the architecture of computer.
is it called memory only computer.
 
i studied in computer architecture that we can build a computer without the use of CPU.

using only memory and its addressing, what is the name of that kind of computer ?
Did you ask the instructor?

Then one could use memory as micro code to manipulate the internal buses and registers. I guess that would make it a micro coded machine.

Your are going to need an address counter. Actually 2 of them. One for the user and one for the micro code.

One can do the math with table lookups. That architecture is called CADET. Can't Add Don't even Try.

Thats all I got right now.
 
thnx
who is instructor ?
 
lol distributed processing ..
this is getting out of hand
 
dang i dont have credit or debit card, cant purchase that can you pls tell me the name of the chapter or the topic which i can google
 
according to index of the book, the chapter is called "The Stored Program Machine".
book goes over introduction to digital logic, design and comparison of FSM and true computer system.
chapter 2 goes over design of 'computer system' and steps to make one. the process is well described and rather simple,
i consists of output register, program counter, memory, instruction decoder etc.

when I was in school, we had to build one just like it and make our own instructions.

here is one of graphs showing simple concept with just one input (LOC), and memory to hold program. instruction decoder is only three gates and an inverter.

this was just warm-up, following chapters go over PIC hardware. hope it helps
 

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thanks
 
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