Clock Hack Gives DEC Rainbow A New Lease On Life

September 12, 2023 by Dan Maloney 21 Comments

In retrocomputing circles, it’s often the case that the weirder and rarer the machine, the more likely it is to attract attention. And machines don’t get much weirder than the DEC Rainbow 100-B, sporting as it does both Z80 and 8088 microprocessors and usable as either a VT100 terminal or as a PC with either CP/M or MS-DOS. But hey — at least it got the plain beige box look right.

Weird or not, all computers have at least a few things in common, a fact which helped [Dr. Joshua Reichard] home in on the problem with a Rainbow that was dead on arrival. After a full recapping — a prudent move given the four decades since the machine was manufactured — the machine failed to show any signs of life. The usual low-hanging diagnostic fruit didn’t provide much help, as both the Z80 and 8088 CPUs seemed to be fine. It was then that [Joshua] decided to look at the heartbeat of the machine — the 24-ish MHz clock shared between the two processors — and found that it was flatlined.

Unwilling to wait for a replacement, [Joshua] cobbled together a temporary clock from an Arduino Uno and an Si5351 clock generator. He connected the output of the card to the main board, whipped up a little code to generate the right frequency, and the nearly departed machine sprang back to life. [Dr. Reichard] characterizes this as a “defibrillation” of the Rainbow, and while one hates to argue with a doctor — OK, that’s a lie; we push back on doctors all the time — we’d say the closer medical analogy is that of fitting a temporary pacemaker while waiting for a suitable donor for a transplant.

This is the second recent appearance of the Rainbow on these pages — [David] over at Usagi Electric has been working on the graphics on his Rainbow lately.

Otis Boykin’s Precision Passives Propelled The Pacemaker

September 16, 2020 by Kristina Panos 11 Comments

The simplest ideas can be the ones that change the world. For Otis Boykin, it was a new way to make wirewound precision resistors. Just like that, he altered the course of electronics with his ideas about what a resistor could be. Now his inventions are in everything from household appliances and electronics to missile guidance computers.

While we like to geek out about developments in resistor tech, Otis’ most widely notable contribution to electronics is the control unit he designed for pacemakers, which regulate a person’s heartbeat. Pacemakers are a real-time clock for humans, and he made them more precise than ever.

Street Smarts and Book Smarts

Otis Frank Boykin was born August 29th, 1920 in Dallas, Texas to Sarah and Walter Boykin. Otis’ father was a carpenter who later became a preacher. His mother Sarah was a maid, and she died of heart failure when Otis was only a year old.

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Radio Controlled Pacemakers Are Easily Hacked

May 27, 2017 by Jack Laidlaw 40 Comments

Doctors use RF signals to adjust pacemakers so that instead of slicing a patient open, they can change the pacemakers parameters which in turn avoids unnecessary surgery. A study on security weaknesses of pacemakers (highlights) or full Report (PDF) has found that pacemakers from the main manufacturers contain security vulnerabilities that make it possible for the devices to be adjusted by anyone with a programmer and proximity. Of course, it shouldn’t be possible for anyone other than medical professionals to acquire a pacemaker programmer. The authors bought their examples on eBay.

They discovered over 8,000 known vulnerabilities in third-party libraries across four different pacemaker programmers from four manufacturers. This highlights an industry-wide problem when it comes to security. None of the pacemaker programmers required passwords, and none of the pacemakers authenticated with the programmers. Some home pacemaker monitoring systems even included USB connections in which opens up the possibilities of introducing malware through an infected pendrive.

The programmers’ firmware update procedures were also flawed, with hard-coded credentials being very common. This allows an attacker to setup their own authentication server and upload their own firmware to the home monitoring kit. Due to the nature of the hack, the researchers are not disclosing to the public which manufacturers or devices are at fault and have redacted some information until these medical device companies can get their house in order and fix these problems.

This article only scratches the surface for an in-depth look read the full report. Let’s just hope that these medical companies take action as soon as possible and resolve these issue’s as soon as possible. This is not the first time pacemakers have been shown to be flawed.

Swallow The Doctor — The Present And Future Of Robots Inside Us

November 30, 2015 by Dan Maloney 7 Comments

I recently finished the Silo series by Hugh Howey, a self-published collection of novellas that details life in a near-future, post-apocalyptic world where all that remains of humanity has been stuffed into subterranean silos. It has a great plot with some fun twists and plenty of details to keep the hacker and sci-fi fan entertained.

One such detail is nanorobots, used in later volumes of the series as both life-extending tools and viciously specific bio-weapons. Like all good reads, Silo is mainly character driven, so Howey doesn’t spend a lot of eInk on describing these microscopic machines – just enough detail to move the plot along. But it left me wondering about the potential for nanorobotics, and where we are today with the field that dates back to Richard Feynman’s suggestion that humans would some day “swallow the doctor” in a 1959 lecture and essay called “There’s Plenty of Room at the Bottom.”

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Reusing An Old Pacemaker As A Flash Timer

January 19, 2012 by Mike Nathan 26 Comments

pacemaker-flash-timer

Most people use pacemakers to, you know, keep their heart pumping at a steady rhythm. [David Prutchi] on the other hand has found a pretty novel use for some of the old pacemakers he has in his collection.

We really had no idea that pacemakers had uses outside the world of medicine, but [David] has taken advantage of their reliability in one of his favorite hobbies – high speed photography. In a darkened room, he set up an infrared barrier which feeds its signal to the atrium input of an old pacemaker. The signal is relayed through the ventricular output, which then fires his camera’s flash.

The pacemaker allows [David] to set an “AV” delay, which is the interval between when the atrium input receives an electrical impulse and when that signal is repeated from the ventricular output. This allows him to finely tune how much time elapses from when a drop of milk breaks the IR barrier to when his flash actuates.

We think this is a pretty cool way to reuse an old pacemaker, but check out the shots he has captured and judge for yourself.

Defcon 16: Pacemaker-B-Gone

August 9, 2008 by Benjamin Eckel 24 Comments

A collaboration of various medical researchers in the academic field has led to proof that pacemakers can be remotely hacked with simple and accessible equipment. [Kevin Fu], an associate professor at the University of Massachusetts at Amherst, led the team. [Kevin] first tried to get documentation from the manufacturers, believing they would support the effort, but they were not interested in helping. They were forced to get access to an old pacemaker and reverse engineer it. They found that the communication protocol used to remotely program the device was unencrypted. They then used a GNU radio system to find access to some of the machine’s reprogrammable functions, including accessing patient data and even turning it off.

Although this was only done with one particular pacemaker, it proves the concept and should be taken seriously by the medical companies who produce these devices. If you are interested in the technical aspects, check out the paper the team released in May disclosing the methods.