Motorola 6800

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See [http://www.visual6502.org/images/pages/Motorola_6800_die_shots.html here] for an overview of the chip and the photographs we have of the die.  As of late March 2011 we have vectorised polygons and a transistor level netlist, which we hope to publish soon.
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See [http://en.wikipedia.org/wiki/Motorola_6800 Wikipedia] for good technical and historical information and references on the Motorola 6800.
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Here are JPEG images of the recaptured polygons - these may be easier to explore than the svg format:
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=== Chip Photos ===
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We [http://www.visual6502.org/images/pages/Motorola_6800_die_shots.html depackaged, deprocessed and photographed] a later depletion-load version of the chip, which shows signs in the layout of the previous enhancement-load version.  Ijor then captured polygons from the photos - here are JPEG images, which may be easier to explore than the svg format:
[[File:Mc6800a-Layout-svg-150h.jpg|link=http://www.visual6502.org/images/6800/mc6800a-Layout-svg-1200w.jpg|Medium size]]
[[File:Mc6800a-Layout-svg-150h.jpg|link=http://www.visual6502.org/images/6800/mc6800a-Layout-svg-1200w.jpg|Medium size]]
[[File:Mc6800a-Layout-svg-150h.jpg|link=http://www.visual6502.org/images/6800/mc6800a-Layout-svg-8980w.jpg|Full size (14Mbyte)]]
[[File:Mc6800a-Layout-svg-150h.jpg|link=http://www.visual6502.org/images/6800/mc6800a-Layout-svg-8980w.jpg|Full size (14Mbyte)]]
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We have a JavaScript simulator available here [http://visual6502.org/JSSim/expert-6800.html?nosim=t (graphical mode)] [http://visual6502.org/JSSim/expert-6800.html?graphics=f&loglevel=4&steps=20 (non-graphical mode)]
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=== Chip Simulator ===
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Interesting features (more detail to be added)
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From the polygons we were able to construct a netlist, and Segher has labelled many of interior nodes, so we can present a have a JavaScript simulator: [http://visual6502.org/JSSim/expert-6800.html?nosim=t (graphical mode)] [http://visual6502.org/JSSim/expert-6800.html?graphics=f&loglevel=4&steps=20 (non-graphical mode)]
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* register circuit
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* data latch circuit
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=== Points of Interest ===
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We've found these interesting features (more detail to be added)
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* register circuit using resistive feedback and enhancement-style pullups
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* data latch circuit using weak feedback transistor
* clock pulse shaping
* clock pulse shaping
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* bus pullup
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* resistive bus pullup
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* carry chain
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* Manchester carry chain
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=== Block Diagram ===
Here's the block diagram from the [http://www.google.com/patents?id=6OkAAAAAEBAJ&zoom=4&pg=PA3#v=onepage&q&f=false 1976 topology patent] (See also [http://www.freepatentsonline.com/4090236.pdf this later patent.]):
Here's the block diagram from the [http://www.google.com/patents?id=6OkAAAAAEBAJ&zoom=4&pg=PA3#v=onepage&q&f=false 1976 topology patent] (See also [http://www.freepatentsonline.com/4090236.pdf this later patent.]):
[[File:M6800-arch.png]]
[[File:M6800-arch.png]]
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=== Resources ===
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* [http://en.wikipedia.org/wiki/Motorola_6800 Wikipedia article]
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* [http://people.sinclair.edu/nickreeder/eet252/datasheets/MC6800.pdf Datasheet (pdf)] (Nick Reeder at Sinclair Community College)
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* [ftp://ftp.comlab.ox.ac.uk/pub/Cards/txt/6800.txt Instruction set summary] (comlab at Oxford University)
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* [http://www.sbprojects.com/sbasm/6800.htm#model Programming Model] (website for SB-assembler)

Revision as of 19:24, 9 April 2011

See Wikipedia for good technical and historical information and references on the Motorola 6800.

Contents

Chip Photos

We depackaged, deprocessed and photographed a later depletion-load version of the chip, which shows signs in the layout of the previous enhancement-load version. Ijor then captured polygons from the photos - here are JPEG images, which may be easier to explore than the svg format:

Medium size Full size (14Mbyte)

Chip Simulator

From the polygons we were able to construct a netlist, and Segher has labelled many of interior nodes, so we can present a have a JavaScript simulator: (graphical mode) (non-graphical mode)

Points of Interest

We've found these interesting features (more detail to be added)

  • register circuit using resistive feedback and enhancement-style pullups
  • data latch circuit using weak feedback transistor
  • clock pulse shaping
  • resistive bus pullup
  • Manchester carry chain

Block Diagram

Here's the block diagram from the 1976 topology patent (See also this later patent.): M6800-arch.png

Resources

Personal tools