When I look inside a chip from the popular series, I know what to expect: a fairly simple die, implemented in a straightforward, cost effective way. However, when I looked inside a military grade chip built by Integrated Device Technology IDT I found a very unexpected layout: over ...

   In , Intel introduced the microprocessor, a variant of the bit processor. IBM’s decision to use the processor in the IBM PC was a critical point in computer history, leading to the dominance of the x architecture that continues to the present. One way that the ...

   What would you say is the first microcomputer The Apple I from The Altair from Perhaps the lesser known Micral N or Q How about the Arma Micro Computer from way back in . The Arma Micro Computer was a compact pound transistorized computer, designed for...

   The Bendix Central Air Data Computer CADC is an electromechanical analog computer that uses gears and cams for its mathematics. It was a key part of military planes such as the F and the F fighters, computing airspeed, Mach number, and other air data . The rotating gears are powered by...

   MathJax tex: inlineMath: ’ ’, ’ ’ , ’ ’, ’ ’ , svg: fontCache: ’global’ , chtml: displayAlign: ’left’ ; MathJax.Hub.Config HTML CSS : scale: ; .MathJax font size: em important In the s, many fighter planes used the ...

   The processor was Intel’s most complex processor at the time, with , transistors. Intel had scheduled person years to design the processor, but it was falling behind schedule. The design team decided to automate chunks of the layout, developing automatic place and route ...

   I recently came across an interesting die photo of a Soviet chip, probably designed in the s. This article provides an introductory guide to reverse engineering CMOS circuits, using this chip as an example. Although the chip looks like a tangle of lines at first, its large features and simple...

   MathJax tex: inlineMath: ’ ’, ’ ’ , ’ ’, ’ ’ , svg: fontCache: ’global’ , chtml: displayAlign: ’left’ ; MathJax.Hub.Config HTML CSS : scale: ; .MathJax font size: em important The Bendix Central Air Data Computer CADC ...

   I’ve studied a lot of chips from the s and s, so I usually know what to expect. But an Ethernet chip from had something new: a strange layer of yellow wiring on the die. After some study, I learned that the yellow wiring is a second layer of resistive polysilicon, used in the chip’s...

   While repairing an eight inch HP floppy drive, we found that the problem was a broken interface chip. Since the chip was bad, I decapped it and took photos. This chip is very unusual: instead of a silicon substrate, the chip is formed on a base of sapphire, with silicon and metal wiring on top. As...

   Intel’s processor was an important advance in the x architecture, not only moving to a bit processor but also switching to a CMOS implementation. I’ve been reverse engineering parts of the chip and came across two interesting and completely different circuits that the uses...

   The Intel processor was a large step from the processor, moving x to a bit architecture. The also dramatically improved the performance of shift and rotate operations by adding a barrel shifter , a circuit that can shift by multiple bits in one step. The die photo below...

   Processors are driven by a clock, which controls the timing of each step inside the chip. In this blog post, I’ll examine the clock generation circuitry inside the Intel processor. Earlier processors such as the were simpler, using two clock phases internally. The Intel ...

   The groundbreaking Intel processor was the first bit processor in the x line. It has numerous internal registers: general purpose registers, index registers, segment selectors, and more specialized registers. In this blog post, I look at the silicon die of the and explain how...

   Introduced in , Ethernet is the predominant way of wiring computers together. Chips were soon introduced to handle the low level aspects of Ethernet: converting data packets into bits, implementing checksums, and handling network collisions. In , Intel announced the i Ethernet LAN...

   You might think of the Intel processor as just an early processor in the x line, but the was a critical turning point for modern computing in several ways. First, the moved the x architecture to bits, defining the dominant computing architecture for the rest of the th...

   MathJax tex: inlineMath: ’ ’, ’ ’ , ’ ’, ’ ’ , svg: fontCache: ’global’ , chtml: displayAlign: ’left’ ; MathJax.Hub.Config HTML CSS : scale: ; .MathJax font size: em important How did fighter planes in the s perform...

   A key concept for a processor is the management of state , information that persists over time. Much of a computer is built from logic gates, such as NAND or NOR gates, but logic gates have no notion of time. Processors also need a way to hold values, along with a mechanism to move from step to...

   hilite cursor:zoom in a:link img.hilite, a:visited img.hilite color: fff; a:hover img.hilite color: f ; The Intel processor started the x architecture that is still extensively used today. The has some quirky characteristics: it is little endian, has a parity flag, and...

   hilite cursor:zoom in a:link img.hilite, a:visited img.hilite color: fff; a:hover img.hilite color: f ; The Intel microprocessor revolutionized computing by founding the x architecture that continues to this day. One of the lesser known features of the is the hold...

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   hilite cursor:zoom in a:link img.hilite, a:visited img.hilite color: fff; a:hover img.hilite color: f ; The Intel microprocessor started the x architecture that continues to this day. In this blog post, I’m focusing on a small part of the chip: the address and data pins...

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