New Articles (Page 116)
To stay up to date you can also follow on Mastodon.
π Motorola 6800
The 6800 ("sixty-eight hundred") is an 8-bit microprocessor designed and first manufactured by Motorola in 1974. The MC6800 microprocessor was part of the M6800 Microcomputer System that also included serial and parallel interface ICs, RAM, ROM and other support chips. A significant design feature was that the M6800 family of ICs required only a single five-volt power supply at a time when most other microprocessors required three voltages. The M6800 Microcomputer System was announced in March 1974 and was in full production by the end of that year.
The 6800 has a 16-bit address bus that can directly access 64Β KB of memory and an 8-bit bi-directional data bus. It has 72 instructions with seven addressing modes for a total of 197 opcodes. The original MC6800 could have a clock frequency of up to 1Β MHz. Later versions had a maximum clock frequency of 2Β MHz.
In addition to the ICs, Motorola also provided a complete assembly language development system. The customer could use the software on a remote timeshare computer or on an in-house minicomputer system. The Motorola EXORciser was a desktop computer built with the M6800 ICs that could be used for prototyping and debugging new designs. An expansive documentation package included datasheets on all ICs, two assembly language programming manuals, and a 700-page application manual that showed how to design a point-of-sale terminal (a computerized cash register) around the 6800.
The 6800 was popular in computer peripherals, test equipment applications and point-of-sale terminals. It also found use in arcade games and pinball machines. The MC6802, introduced in 1977, included 128 bytes of RAM and an internal clock oscillator on chip. The MC6801 and MC6805 included RAM, ROM and I/O on a single chip and were popular in automotive applications. The Motorola 6809 was an updated compatible design.
Discussed on
- "Motorola 6800" | 2022-06-24 | 115 Upvotes 122 Comments
π Detention of Mark Bernstein
On 11 March 2022, Mark Izraylevich Bernstein (Russian: ΠΠ°ΡΠΊ ΠΠ·ΡΠ°ΠΉΠ»Π΅Π²ΠΈΡ ΠΠ΅ΡΠ½ΡΡΠ΅ΠΉΠ½), a Belarusian blogger and editor of the Russian-language Wikipedia based in Minsk, was detained by the Belarusian GUBOPiK security force after online accusations of violating the 2022 Russian fake news law for his editing of Wikipedia articles on the topic of the 2022 Russian invasion of Ukraine. He was sentenced to 15 days' administrative arrest under Article 24.3 of the Administrative Code of Belarus (for disobedience to police officers).
Discussed on
- "Detention of Mark Bernstein" | 2022-06-23 | 112 Upvotes 21 Comments
π Competent Man
In literature, the competent man is a stock character who exhibits a very wide range of abilities and knowledge, making him a form of polymath. While not the first to use such a character type, the heroes and heroines of Robert A. Heinlein's fiction (with Jubal Harshaw being a prime example) generally have a wide range of abilities, and one of Heinlein's characters, Lazarus Long, gives a wide summary of requirements:
A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyse a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects.
The competent man, more often than not, is written without explaining how he achieved his wide range of skills and abilities. When such characters are young, there is often not much explanation as to how they acquired so many skills at an early age.
Discussed on
- "Competent Man" | 2022-06-22 | 12 Upvotes 5 Comments
π Stolperstein
A Stolperstein (pronounced [ΛΚtΙlpΙΛΚtaΙͺn] (listen); plural Stolpersteine; literally "stumbling stone", metaphorically a "stumbling block") is a sett-size, ten-centimetre (3.9Β in) concrete cube bearing a brass plate inscribed with the name and life dates of victims of Nazi extermination or persecution.
The Stolpersteine project, initiated by the German artist Gunter Demnig in 1992, aims to commemorate individuals at exactly the last place of residencyβor, sometimes, workβwhich was freely chosen by the person before he or she fell victim to Nazi terror, euthanasia, eugenics, deportation to a concentration or extermination camp, or escaped persecution by emigration or suicide. As of December 2019, 75,000 Stolpersteine have been laid, making the Stolpersteine project the world's largest decentralized memorial.
The majority of Stolpersteine commemorate Jewish victims of the Holocaust. Others have been placed for Sinti and Romani people (then also called "gypsies"), homosexuals, the physically or mentally disabled, Jehovah's Witnesses, black people, members of the Communist Party, the Social Democratic Party, and the anti-Nazi Resistance, the Christian opposition (both Protestants and Catholics), and Freemasons, along with International Brigade soldiers in the Spanish Civil War, military deserters, conscientious objectors, escape helpers, capitulators, "habitual criminals", looters, and others charged with treason, military disobedience, or undermining the Nazi military, as well as Allied soldiers.
Discussed on
- "Stolperstein" | 2022-06-18 | 445 Upvotes 170 Comments
π HAL/S Syntax
HAL/S (High-order Assembly Language/Shuttle) is a real-time aerospace programming language compiler and cross-compiler for avionics applications used by NASA and associated agencies (JPL, etc.). It has been used in many U.S. space projects since 1973 and its most significant use was in the Space Shuttle program (approximately 85% of the Shuttle software is coded in HAL/S). It was designed by Intermetrics in 1972 for NASA and delivered in 1973. HAL/S is written in XPL, a dialect of PL/I. Although HAL/S is designed primarily for programming on-board computers, it is general enough to meet nearly all the needs in the production, verification, and support of aerospace and other real-time applications. According to documentation from 2005, it was being maintained by the HAL/S project of United Space Alliance.
Discussed on
- "HAL/S Syntax" | 2022-06-18 | 38 Upvotes 15 Comments
π Puppy Pregnancy Syndrome
Puppy pregnancy syndrome (PPS) is a psychosomatic illness in humans brought on by mass hysteria.
The syndrome is thought to be localized in villages in several states of India, including West Bengal, Assam, Bihar, Jharkhand, Orissa, and Chhattisgarh, and has been reported by tens of thousands of individuals. It is far more prevalent in areas with little access to education.
People suffering from PPS believe that shortly after being bitten by a dog, puppies are conceived within their abdomen. This is said to be especially likely if the dog is sexually excited at the time of the attack. Victims are said to bark like dogs and have reported being able to see the puppies inside them when looking at water or hear them growling in their abdomen. It is believed that the victims will eventually die β especially men, who will give birth to their puppies through the penis.
Witch doctors offer oral cures, which they claim will dissolve the puppies, allowing them to pass through the digestive system and be excreted "without the knowledge of the patient".
Doctors in India have tried to educate the public about the dangers of believing in this condition. Most sufferers are referred to psychiatric services, but in some instances patients fail to take anti-rabies medication before symptom onset, thinking that they are pregnant with a puppy and that folk medicine will cure them. This misbelief is further compounded by witch doctors who state that their medicine will fail if sufferers seek standard treatment.
Some psychiatrists believe that PPS meets the criteria for a culture-bound disorder.
π Link 16
Link 16 is a military tactical data link network used by NATO and nations allowed by the MIDS International Program Office (IPO). Its specification is part of the family of Tactical Data Links.
With Link 16, military aircraft as well as ships and ground forces may exchange their tactical picture in near-real time. Link 16 also supports the exchange of text messages, imagery data and provides two channels of digital voice (2.4Β kbit/s or 16Β kbit/s in any combination). Link 16 is defined as one of the digital services of the JTIDS / MIDS in NATO's Standardization Agreement STANAG 5516. MIL-STD-6016 is the related United States Department of Defense Link 16 MIL-STD.
π Poppy Seed Defence
The poppy seed defence is a commonly cited reason to avoid any sanction for failing a drug test. The defence asserts that a suspect's positive result was a result of the person having consumed poppy seeds prior to taking the test. It has been recognised in medical and legal fields as a valid defence.
π Moon Illusion
The Moon illusion is an optical illusion which causes the Moon to appear larger near the horizon than it does higher up in the sky. It has been known since ancient times and recorded by various cultures. The explanation of this illusion is still debated.
Discussed on
- "Moon Illusion" | 2022-06-12 | 129 Upvotes 71 Comments
π Bioluminescence
Bioluminescence is the production and emission of light by living organisms. It is a form of chemiluminescence. Bioluminescence occurs widely in marine vertebrates and invertebrates, as well as in some fungi, microorganisms including some bioluminescent bacteria, and terrestrial arthropods such as fireflies. In some animals, the light is bacteriogenic, produced by symbiotic bacteria such as those from the genus Vibrio; in others, it is autogenic, produced by the animals themselves.
In a general sense, the principal chemical reaction in bioluminescence involves a light-emitting molecule and an enzyme, generally called luciferin and luciferase, respectively. Because these are generic names, luciferins and luciferases are often distinguished by the species or group, e.g. firefly luciferin. In all characterized cases, the enzyme catalyzes the oxidation of the luciferin.
In some species, the luciferase requires other cofactors, such as calcium or magnesium ions, and sometimes also the energy-carrying molecule adenosine triphosphate (ATP). In evolution, luciferins vary little: one in particular, coelenterazine, is found in 11 different animal phyla, though in some of these, the animals obtain it through their diet. Conversely, luciferases vary widely between different species, which is evidence that bioluminescence has arisen over 40 times in evolutionary history.
Both Aristotle and Pliny the Elder mentioned that damp wood sometimes gives off a glow. Many centuries later Robert Boyle showed that oxygen was involved in the process, in both wood and glowworms. It was not until the late nineteenth century that bioluminescence was properly investigated. The phenomenon is widely distributed among animal groups, especially in marine environments. On land it occurs in fungi, bacteria and some groups of invertebrates, including insects.
The uses of bioluminescence by animals include counterillumination camouflage, mimicry of other animals, for example to lure prey, and signaling to other individuals of the same species, such as to attract mates. In the laboratory, luciferase-based systems are used in genetic engineering and biomedical research. Researchers are also investigating the possibility of using bioluminescent systems for street and decorative lighting, and a bioluminescent plant has been created.
Discussed on
- "Bioluminescence" | 2022-06-12 | 13 Upvotes 8 Comments