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Is microprocessor an integrated circuit???

B

Bradley1234

Jan 1, 1970
0
You can post that it is a can of grapes, but that doesn't make it so.
The vax-11/780 was not a microprocessor. Using microcode does not make a
microprocessor.
Well okay, if you say the definition is micro sized processor, then it
depends on your definition of what the word IS is.

Its a definition that I thought wasnt challenged, micro programmed processor



There are many examples of microprocessors that didn't use microcode.

Hey cool, Im going to learn something new, I like to learn. Even though we
have an arbitrary definition going, where microprocessor might also mean
"purple monkey dishwasher"

PLEASE show an example of a microprocessor that doesnt use microcode

If Im wrong, Ill take back what I said

I know there are "processors" that are mechanical, but strictly a
microprocessor
 
A

Andrew Holme

Jan 1, 1970
0
Bradley1234 said:
PLEASE show an example of a microprocessor that doesnt use microcode

Broadly speaking, it depends whether the microprocessor is RISC or CISC:
RISC (Reduced Instruction Set) processors don't use microcode - they have
"hard-wired" logic; CISC (Complex Instruction Set) processors generally do
have microcode. The exact definitions of RISC and CISC are somewhat
contentious. The 6502, which is often said to be the first RISC processor,
was not microcoded.
 
S

Spehro Pefhany

Jan 1, 1970
0
Well okay, if you say the definition is micro sized processor, then it
depends on your definition of what the word IS is.

Its a definition that I thought wasnt challenged, micro programmed processor





Hey cool, Im going to learn something new, I like to learn. Even though we
have an arbitrary definition going, where microprocessor might also mean
"purple monkey dishwasher"

PLEASE show an example of a microprocessor that doesnt use microcode

If Im wrong, Ill take back what I said

I know there are "processors" that are mechanical, but strictly a
microprocessor

Scenix (now Ubicom) for one. Microchip sued them and Micon Design
Technology in Munich District Court, claiming copyright infringement
of their microcode. Their defense was that they didn't have any.

And a startup company named TeraGen apparently made a version of the
venerable 8051 without microcode.

And, apparently, the Alpha.

But I think most microprocessor cores do use microcode. CISC ones
certainly do, RISC ones may not.


Best regards,
Spehro Pefhany
 
S

Spehro Pefhany

Jan 1, 1970
0
Broadly speaking, it depends whether the microprocessor is RISC or CISC:
RISC (Reduced Instruction Set) processors don't use microcode - they have
"hard-wired" logic; CISC (Complex Instruction Set) processors generally do
have microcode. The exact definitions of RISC and CISC are somewhat
contentious. The 6502, which is often said to be the first RISC processor,
was not microcoded.

Are you sure? There are claims in Google Groups that die photos show a
fairly large microcode ROM on the chip, and many of the instructions
take quite a few more than the minimum 2 cycles (3, 4, 5, 6 or 7).

The PIC is often called "RISC", but it is apparently microcoded.


Best regards,
Spehro Pefhany
 
T

TCS

Jan 1, 1970
0
But I think most microprocessor cores do use microcode. CISC ones
certainly do, RISC ones may not.

However, that fact is irrelevent. Most minicomputers and many mainframes
use microcode as well and many microprocessors do not.
 
T

TCS

Jan 1, 1970
0
Broadly speaking, it depends whether the microprocessor is RISC or CISC:
RISC (Reduced Instruction Set) processors don't use microcode - they have
"hard-wired" logic; CISC (Complex Instruction Set) processors generally do
have microcode. The exact definitions of RISC and CISC are somewhat
contentious. The 6502, which is often said to be the first RISC processor,
was not microcoded.



Nor were the 1802, 4004, 8080, z80, or z8000. I believe the 8085 and
6800 were hard coded as well.

There's a point when a processor is too complex to hard code. The Z8000
was the last of the hard coded microprocessors and it was a failure due to
it's numerous bugs.
 
B

Bradley1234

Jan 1, 1970
0
Can you show links? drawings/pdfs or ?

The original Alpha risc? or which?

Scenix (now Ubicom) for one. Microchip sued them and Micon Design
Technology in Munich District Court, claiming copyright infringement
of their microcode. Their defense was that they didn't have any.

And a startup company named TeraGen apparently made a version of the
venerable 8051 without microcode.

And, apparently, the Alpha.

But I think most microprocessor cores do use microcode. CISC ones
certainly do, RISC ones may not.


Best regards,
Spehro Pefhany
http://www.speff.com
 
K

Ken Smith

Jan 1, 1970
0
Bradley1234 <[email protected]> said:
Answer: it can be.

ummmm ummm let me guess without the ontext I've got to assume that this is
a comment about Canadian bee keepers developing an new breed called the
"Can Bee".. Am I right?

Some microprocessors are made with discrete components,
You must be thinking about the special ones for encription. Discrete
components are better for keeping secrets.
but most today are integrated circuits, meaning the components have been
built onto one circuit

No, it means that the bipolars and the mosfets go to school together on
the same data bus.

Microprocessor means: micro programmed processor such that instructions are
processed by referencing internal memory locations and there is a processor
within a processor.

You forgot to mension that this smaller processor has an even smaller on
inside it and so on all the way down to a single atom. At least this is
how the Russians make them.
Most commercial microprocessors are general purpose, meaning the instruction
set gives developers methods to move/control data, but some uPs are specific
and have a limited/specific instruction set

To be more specific, some Reduced Instruction Set Computers (RISC) gain a
great deal of speed at the cost of removing certain instuctions. The
French have just introduced on that takes this to the limit. The NISC (No
Intruction Set Computer) has no instructions and is as a result infinitely
fast.
 
K

Ken Smith

Jan 1, 1970
0
This is simply not accurate. Microprocessors typically operate with
instruction and data fetch modes. When an instruction fetch takes place,
the op code causes a branch to an internal memory of the internal cpu state[/QUOTE]

Specifically not true in the 4004, 4040, CD1802, or Z80.
 
J

John Larkin

Jan 1, 1970
0
When there is a micro engine, using micro instructions, stored in microcode
memory, its a micro processor. There is a clock, internal microcode address
generator, next address logic, mux. Can you name any 8 bit cpu that uses
only hard wired logic??

6800, 6802, 6803, 6805, probably the PICs.

Any RISC processor: SPARC, PowerPC, Arm, Coldfire.

AVR and Dragonball, I think.

The original PDP-11 wasn't microcoded; it had about 550 TTL/MSI chips.

John
 
M

Michael Black

Jan 1, 1970
0
Andrew Holme" ([email protected]) said:
Broadly speaking, it depends whether the microprocessor is RISC or CISC:
RISC (Reduced Instruction Set) processors don't use microcode - they have
"hard-wired" logic; CISC (Complex Instruction Set) processors generally do
have microcode. The exact definitions of RISC and CISC are somewhat
contentious. The 6502, which is often said to be the first RISC processor,
was not microcoded.
The 6502 was never RISC.

It's only after RISC came along that some people thought it just meant
"few instructions" and then decided the 6502 fit that definition.

The 6502 wasn't particularly different from the 6800, or for that matter
the 8080.

Micahel
 
B

Ben Bradley

Jan 1, 1970
0
Well okay, if you say the definition is micro sized processor, then it
depends on your definition of what the word IS is.

Its a definition that I thought wasnt challenged, micro programmed processor

It appears you have two separate computer-related ideas mixed
together, which is pretty understandable since they both use the word
'micro.'
If I recall my computer history, microprogramming (instructions
controlling a CPU by the instruction addressing a wide ROM [or RAM]
whose outputs activate various parts of the CPU) was done many years
before the first microprocesor (a CPU on a single silicon chip) was
made.
If there's a correlation between these two, it's probably negative:
I understand many of the larger mainframe CPU's use microprogramming,
and smaller microprocessors use hard-wired logic exclusively.
 
R

Rich Grise

Jan 1, 1970
0
No it doesn't. It means micro-sized processor. What you're describing also
includes the vax-11/780 whose processor board was hardly a microprocessor.

A microprocessor is nearly always a single chip processor; first one was the
4004; following were the 8080, 6800, 1802, etc. I don't bit slice processors
could be considered a microprocessor.

But there is at least bit-slice processor called a "microprogrammable
processor" where the programmer actually writes a microprogram. It was
used in the "enhanced controller-tester", and they used it to test big ol'
disk drives - like, 600 MB in a unit the size of a desk. It had 8 KB of
TTL SRAM. They could make it emulate whatever kind of computer the drive
was destined to be plugged into.

"Microprogrammed processor" would be appropriate for a bit-slice where
the microprogram is nonvolatile, but if it's all on a chip, it's still
a microprocessor.

I think "the whole processor on one chip" is the definitive difference.

Thanks,
Rich
 
R

Rich Grise

Jan 1, 1970
0
This is simply not accurate. Microprocessors typically operate with
instruction and data fetch modes. When an instruction fetch takes place,
the op code causes a branch to an internal memory of the internal cpu state

Specifically not true in the 4004, 4040, CD1802, or Z80.[/QUOTE]

In the 8008, the basic machine language was almost microcode. The top two
bits selected the function, the next three bits selected an address
register, and the next three bits selected the other address register.
Except for specials, of course, which had their own logic to decode
them, but there certainly wasn't anything like a "microcontrol store",
unless you consider the hardwiring of the logic itself to be the
microprogram, but that's a stretch.

Microcoding something like would be like using hand grenades on gnats.

Thanks!
Rich
 
C

Chaos Master

Jan 1, 1970
0
To be more specific, some Reduced Instruction Set Computers (RISC) gain a
great deal of speed at the cost of removing certain instuctions. The
French have just introduced on that takes this to the limit. The NISC (No
Intruction Set Computer) has no instructions and is as a result infinitely
fast.

Maybe a SISC (Single Instruction Set Computer) with just NOP or HLT?

[]s
--
Chaos Master®, posting from Canoas, Brazil - 29.55° S / 51.11° W / GMT-
2h / 15m

"He [Babya] is like the Energizer Bunny of hopeless newsgroup
posting....or should that be Energizer bBunny"
- "ceed" on alt.comp.freeware, 24/1/2005

(to some groups: Yes, I use Windows and MS Office. So what?)
 
R

Rich Grise

Jan 1, 1970
0
No, they are not, unless you are calling "the microprocessor chip" a
discrete component. ;-)
The system would be a "minicomputer" some want to say its a mainframe. But
I specifically wrote that the 11/780 "CPU" was a microprocessor because it
executes an internal stored microcode processor

That is a microCODED processor. The specific term, "microprocessor", was
coined to mean "a whole processor on a chip"

A Bit-slice processor is not a microprocessor, no matter how microcoded or
microprogrammable it is, because it doesn't live on ONE CHIP!

Thanks,
Rich
 
R

Rich Grise

Jan 1, 1970
0
Nor were the 1802, 4004, 8080, z80, or z8000. I believe the 8085 and
6800 were hard coded as well.

There's a point when a processor is too complex to hard code. The Z8000
was the last of the hard coded microprocessors and it was a failure due to
it's numerous bugs.

I once saw a write-up on the making of the 6809, and it certainly didn't
look like it had any microcode ROM. Lots of data selectors and registers,
yes, but hardwired.

And I might be just imagining the innards of the 8008, but its instruction
set was so simple and orthogonal, it was as if the "assembly" code was,
itself, microcode.

Having an 8008 with a bunch of LEDs and the ability to step through an
instruction, machine cycle by machine cycle, almost clock by clock, and
watch what the bus and all those status lines are doing is(was?) instructive.
:) Scelbi 8H, BTW.

Cheers!
Rich
 
R

Rich Grise

Jan 1, 1970
0
Well okay, if you say the definition is micro sized processor, then it
depends on your definition of what the word IS is.

Its a definition that I thought wasnt challenged, micro programmed processor

It appears you have two separate computer-related ideas mixed
together, which is pretty understandable since they both use the word
'micro.'
If I recall my computer history, microprogramming (instructions
controlling a CPU by the instruction addressing a wide ROM [or RAM]
whose outputs activate various parts of the CPU) was done many years
before the first microprocesor (a CPU on a single silicon chip) was
made.
If there's a correlation between these two, it's probably negative:
I understand many of the larger mainframe CPU's use microprogramming,
and smaller microprocessors use hard-wired logic exclusively.

So, actually, the microprogram in a microprocessor should actually be
called a picoprogram, or picocode! ;-)

Cheers!
Rich
 
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