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Info for some old (but pretty cool) Micros

Hey guys, how are you?
I'm collecting some information about these old Microprocessors:
Intel 8008, Intel 8080, Intel 8086, Motorola 68000, Zilog Z80 and MOS 6502.

I've been reading different papers but i am not 100% about the word-size, data and address buses; I made a little chart for me, could you please help me to complete it? .

micro_1.jpg

micro_3.jpgmicro_2.jpg


EDIT:

Micros.jpg


EDIT #3: I DID THIS (the first one is not completed but i'm not sure). Could you please help me? Can check my charts?

architecture.jpg
 
Last edited:

rjenkinsgb

Well-Known Member
Most Helpful Member
I've used the Motorola 6800, 6809 68HC11 and 68000 series.

6800 is 8 bit data, 16 bit address (so 0-65535 range).

6809 is 8 or 16 bit data, 16 bit address, as above; the external data bus is still 8 bit, so 16 bit transfers take two memory cycles.
However, it supports relocatable code so with a suitable memory management unit a 6809 system can have eg. a megabyte of RAM.

The HC11 is something of a cross between a 6800 and 6809, 8 bit data bus and 16 bit address, with some internal peripherals and memory, for use in single-chip or minimal component systems & embedded controllers.


The 68000 series support 8/16/32 bit data sizes, with a 32 bit internal data bus and either a 20, 24 or 32 bit address bus.
The address is 32 bit in the CPU, but not all address lines are available as pins, in some package versions.
Likewise, the external data bus could be 8, 16, or 32 bit - so the CPU would do multiple memory cycles if needed to read or write a full word.

If I remember right, the very first release version was the 68008, with 8 bit external data bus and 20 bit external address bus:
 
I've used the Motorola 6800, 6809 68HC11 and 68000 series.

6800 is 8 bit data, 16 bit address (so 0-65535 range).

6809 is 8 or 16 bit data, 16 bit address, as above; the external data bus is still 8 bit, so 16 bit transfers take two memory cycles.
However, it supports relocatable code so with a suitable memory management unit a 6809 system can have eg. a megabyte of RAM.

The HC11 is something of a cross between a 6800 and 6809, 8 bit data bus and 16 bit address, with some internal peripherals and memory, for use in single-chip or minimal component systems & embedded controllers.


The 68000 series support 8/16/32 bit data sizes, with a 32 bit internal data bus and either a 20, 24 or 32 bit address bus.
The address is 32 bit in the CPU, but not all address lines are available as pins, in some package versions.
Likewise, the external data bus could be 8, 16, or 32 bit - so the CPU would do multiple memory cycles if needed to read or write a full word.

If I remember right, the very first release version was the 68008, with 8 bit external data bus and 20 bit external address bus:
Hey dude, how are you?
I've updated my question (i've attached different papers related to the micros). The problem is that i was not able to complete the charts; it gets a little confusing. Can you help me?
 

rjenkinsgb

Well-Known Member
Most Helpful Member
Re. you message:

The D.... lines are the data bus.
The A.... lines are address bus.

AD... lines are multiplexed address and data, so count for both.

The Any 68000 types without an A0, have /LDS and /UDS which select either or both bytes from a 16 bit pair.
 

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