Ken Shirriff's Blog

• Reverse-engineering a vintage comparator chip

  2 days ago Crypto Technology Ken Shirriff's Blog 500

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• Logic chip teardown from a vintage IBM mainframe

  2 weeks ago Crypto Technology Ken Shirriff's Blog 280

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• Two dies in one package: Teardown of a vintage ROM with double the storage

  3 weeks ago Crypto Technology Ken Shirriff's Blog 301

  .hilite {cursor:zoom-in} a:link img.hilite, a:visited img.hilite { color: #fff;} span.wm {text-decoration: underline;...

• Reverse-engineering the standard-cell logic inside a vintage IBM chip

  9-3-2021 Crypto Technology Ken Shirriff's Blog 288

  .hilite {cursor:zoom-in} a:link img.hilite, a:visited img.hilite { color: #fff;} Integrated circuits are often built from standard-cell...

• Germanium transistors: logic circuits in the IBM 1401 computer

  3-3-2021 Crypto Technology Ken Shirriff's Blog 355

  .hilite {cursor:zoom-in} a:link img.hilite, a:visited img.hilite { color: #fff;} How did computers implement logic gates in the 1950s?...

• Strange chip: Teardown of a vintage IBM token ring controller

  28-2-2021 Crypto Technology Ken Shirriff's Blog 363

  .hilite {cursor:zoom-in} a:link img.hilite, a:visited img.hilite { color: #fff;} IBM used some unusual techniques in its integrated...

• Booting the IBM 1401: How a 1959 punch-card computer loads a program

  22-2-2021 Crypto Technology Ken Shirriff's Blog 376

  .hilite {cursor:zoom-in} a:link img.hilite, a:visited img.hilite { color: #fff;} span.wm {text-decoration: underline;...

• Teardown of a quartz crystal oscillator and the tiny IC inside

  20-2-2021 Crypto Technology Ken Shirriff's Blog 373

  .hilite {cursor:zoom-in} a:link img.hilite, a:visited img.hilite { color: #fff;} The quartz oscillator is an important electronic...

• A one-bit processor explained: reverse-engineering the vintage MC14500B

  6-2-2021 Crypto Technology Ken Shirriff's Blog 347

  .hilite {cursor:zoom-in} a:link img.hilite, a:visited img.hilite { color: #fff;} The Motorola MC14500B 1 is a 1-bit processor...

• IBM paperweight teardown: Reverse-engineering 1970s memory chips

  30-1-2021 Crypto Technology Ken Shirriff's Blog 337

  .hilite {cursor:zoom-in} a:link img.hilite, a:visited img.hilite { color: #fff;} I recently received a vintage IBM paperweight from the...

• Examining a technology sample kit: IBM components from 1948 to 1986

  23-1-2021 Crypto Technology Ken Shirriff's Blog 588

  .hilite {cursor:zoom-in} a:link img.hilite, a:visited img.hilite { color: #fff;} I recently received a vintage display box used by IBM to...

• Reverse-engineering a low-power LED flasher chip

  9-1-2021 Crypto Technology Ken Shirriff's Blog 611

  .hilite {cursor:zoom-in} a:link img.hilite, a:visited img.hilite { color: #fff;} How do you make an LED blink? A vintage way is the...

• Reverse-engineering an early calculator chip with four-phase logic

  26-12-2020 Crypto Technology Ken Shirriff's Blog 866

  .hilite {cursor:zoom-in} a:link img.hilite, a:visited img.hilite { color: #fff;} In 1969, high-density MOS integrated circuits were...

• Reverse-engineering the clock chip in the first MOS calculator

  20-12-2020 Crypto Technology Ken Shirriff's Blog 632

  .hilite {cursor:zoom-in} a:link img.hilite, a:visited img.hilite { color: #fff;} In 1969, Sharp introduced the first calculator built from...

• Reverse engineering RAM storage in early Texas Instruments calculator chips

  28-11-2020 Crypto Technology Ken Shirriff's Blog 895

  .hilite {cursor:zoom-in} a:link img.hilite, a:visited img.hilite { color: #fff;} Texas Instruments introduced the first commercial...