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Month: January 2022

Best Oculus Quest 2 Link cables

Best Oculus Quest 2 Link cables

I just upgraded from the older HTC Vive to the Oculus Quest 2. The Quest’s wireless operation without needing all the cables and sensors around your room was a huge improvement. One big shortcoming, however, is the 1 meter USB-C cable. It is ok for charging, but far too short for using the PC connected VR Oculus Link functionality.

The Quest II gets about 2-3 hours on battery. This is ok in many cases, but I definitely could kill it in a heavy gaming session. You can buy additions like the Oculus Quest 2 Elite Strap with battery that doubles your battery time – or go as far as the VR Power 2 that can give you up to 8-10 hours.

But for PC VR, you need a data cable. The longer official Oculus Quest II cable is 16ft/5m long and has a great angled attachment with velcro – but runs a eye popping $79. There are alternatives, but you need to get a high quality cable that does both power and data. Enter Android Central that gives you a bunch of great options.

In the end, I went with the TNE 16ft Link Cable for Oculus Quest 2/Quest VR Type C Cable for $18. It also has the side mount plug with velcro strap like the official one. It has fit and worked perfectly so far, and I also have about $60 to spend on games.

Lickable TV

Lickable TV

Professor Homei Miyashita at Meiji University in Japan has developed a monitor that can imitate on-screen flavors, appropriately naming it Taste The TV (TTTV).

How does it work? It uses a carousel of ten different flavor canisters that can mix the basic flavor building blocks in different proportions to create a variety of tastes, This is sprayed on a hygienic film overlaying a flatscreen which then rolls down much like those old continuous/circular cloth towel dispensers.

Memory CAS latency and true speed

Memory CAS latency and true speed

How do you evaluate how fast a stick of ram is? Many people look at the raw frequency, others CAS latency, and others transfer rate.

As this article outlines, you need to consider both speed AND latency.

For speed (MT/s), this is fairly straightforward, higher is better. But that is only half the equation. The latency of access also matters. Latency is reported as the CAS time – but that is reporting only the total number of clock cycles before access. This can be misleading by itself, because it’s just a number of cycles – not how LONG that time is.

To get an apples-to-apples comparison on latency, we need to look at latency in terms of nanoseconds – not clock cycles. To calculate a module’s latency in nanoseconds, simple multiply clock cycle duration by the total number of clock cycles.

latency (ns) = clock cycle time (ns) x number of clock cycles

Otherwise, you may not be getting much of an improvement at all. Youtube testers often find little difference between different sticks of ram because they might be focusing on faster CAS latency but not doing the whole equation. The table below shows some examples and why you need to pay attention to both speed and CAS timing.

TechnologySpeed (MT/s)Clock Cycle Time(ns)CAS LatencyLatency (ns)
DDR418661.071313.93
DDR421330.941514.06
DDR424000.831714.17
DDR426660.751914.25
DDR429330.682114.32
DDR432000.622213.75
DDR548000.424016.67

So what is the recommendation?

  • Step 1: Identify the highest memory speed supported by both your processor and motherboard (including overclocking profiles).
  • Step 2: Select the lowest latency memory that fits within your budget at that speed, remembering that a superior (i.e. lower) latency means superior system performance.

Here’s some additional information about differences between DDR speeds.

Cracking the Zodiac killer’s code

Cracking the Zodiac killer’s code

Until 2020, the 340 character cipher remained un-decrypted. There have been no end to the theories about the meaning of the code and the identity of its author from would-be sleuths. With the solution text now out and standing up to scrutiny, it’s a wonderful reminder that internet sleuths need to be taken with a grain of salt.

One of these sleuths, Sam Blake, decided to contact programmer David Oranchak of Roanoke, Virginia after he gave a talk on it at the annual meeting of the American Cryptogram Association. Blake was particularly intrigued by the idea of homophonic substitution where one letter might be swapped for more than one symbol and then re-arranged in a systematic way. This generated a whole host of new ways to read the cypher.

Here’s Oranchak’s talk:

Oranchak took what he’d found to Jarl van Eycke, a Belgian warehouse worker and codebreaker who’d written AZdecrypt, software used for decoding homophonic substitutions. Van Eycke used an updated version of his software to churn through the possibilities. Using misspellings and characteristics from Zodiac’s previous writings things started falling into place.

The code used a tremendous amount of computing power, power that was definitely not available in 1960’s. The techniques involved in cracking it weren’t like the ones used in modern cryptography, so it’s explains why few people have used such statistical models on what is essentially a one-off code.

Oranchak sent their solution to contacts at the FBI, and by the end of 2020, the FBI had verified the methodology and results. In March 2021, Blake wrote about how he’d used Mathematica, a math software package, for his part, and in January, van Eycke made headlines again when he cracked an unsolved 386-year-old code composed by a Dutch scientist.

You can read more about the journey here, or check out the 9 part series about solving the code on Oranchak’s youtube channel.