2019-09-04 (Wednesday)

Today, I learned that:

There is finally something really BIG happening in the world of serial communication between electronic devices. Last Thursday, 2019-08-29, was officialized the release of a new version of the popular USB interface, version 4, USB4 to be short, with a maximum data rate of 40 Gbit/s. See also reference #1 below.

From RS-232 to USB4

So, what is so special with this version then? Well, it seems that we now, almost 60 years after the RS-232 serial protocol was introduced, have returned to only one standard, regardless of the brand of the device.

It all started in 1960, when the American industry organisation EIA (Electronic Industries Association) introduced the RS-232 standard, initially to be used between electromechanical teletypewriters as DTEs (data terminal equipment) and modems as DCEs (data circuit-terminating/communication equipment). According to today’s standards, it was extremely slow, maximum 20 kbits/s.

RS-232 had some successors, such as RS-422 and RS-485, where both the speed and maximum cable length had been improved. For example, RS-422 is specified for a maximum bitrate of 10 Mbits/s and a maximum cable length of 1500 m.

We now jump to the 1990s, when the emerging personal computer (PC) industry found that maintaining the RS-232 communication was not feasible. There were then started two different initiatives to make communication between a PC and its peripherals much easier and faster. On January 1, 1996, was released the first version of the universal serial bus (USB). It had been developed by a consortium of companies such as Compaq, DEC, IBM, Intel, Microsoft, NEC, and Nortel. The data rate of USB 1.0 was 12 Mbits/s, which was improved to 480 Mbits/s with version 2.0 in 2001 and 5 Gbits/s through USB 3.0 in 2014, 10 Gbits/s by USB 3.1 in 2014, and 20 Gbits/s specified by USB 3.2 in 2017.

As you can see above, Apple did not participate in the USB consortium. Instead they had decided to develop their own communication interface, and attracted other companies such as Sony, Panasonic, Philips, LG, Toshiba, Hitachi, Canon, Thomson, and Texas Instruments. This group developed what came to be known as FireWire 400, aka standard IEEE 1394-1995. The data rate of this version was a maximum of 400 Mbits/s in half-duplex mode. It was followed by FireWire 800, which reached the speed of its name in 2006. However, Steve Jobs declared that FireWire was dead in 2008 when many camcorders were still using USB 2.0, instead of the faster FireWire.

Intel, which as you saw before already was a leading force in the USB consortium, now started to develop a new hardware interface together with Apple. It was dubbed Thunderbolt, and the first version appeared on MacBook Pro computers in 2011. Sony also used it in a Vaio line of notebooks in 2011. It was later followed by Thunderbolt 2 in 2013, with a maximum data rate of 20 Gbits/s.

And then, in 2016, Thunderbolt 3 was introduced, and as of now we can see that both standards are coming closer to each other, because they share the same USB-C connector. Intel decided in April 2019 to release the Thunderbolt without charging royalties from the companies who would use it, and that was the signal to finally use Thunderbolt 3 as a starting point for the specification of USB 4.

Will this mean that there is now unanimity in the electronics industry to start using only USB 4? Let us hope so, and that we will see the concrete result starting to appear in about a year or so.

There is much more to be said about this interesting topic of data communication, please see references # 2 through 7 below for details.

If you can’t beat them, join them!

A big problem in the crazy traffic in major cities around the world is of course that so many different categories of people on the move need to share the same physical space. Maybe the most troublesome is when motorbikes try to squeeze their way through in the small corridors between the cars. In 1997, when the most recent Brazilian Code for traffic was published, it permitted that they could do so, contrary to safety measures. And as a consequence, every day quite a few of those bikers are involved in severe accidents, even deaths.

If you can’t beat them, join them! In order to reduce the conflict between cars and motorcycles, in the largest avenues in São Paulo have been implemented a buffer zone, exclusive to the bikers, in front of the pedestrian crossing. That way, they can race off without messing with the cars. Photo taken at Avenida Ipiranga on 2019-08-08.

However, one of the ways to mitigate somewhat this conflict was created in 2013 in São Paulo. You can see it in the photo above, taken downtown on 2019-08-09 at Avenida Ipiranga. It shows that motorbikers and other bikers, as well, have a privileged zone in front of the cars, when they need to stop for a red light. That way, when the light turns into green, they can speed away without needing to negotiate space with the car drivers. This method is called “Frente segura”, which means ‘Safe front’. More about it can be seen in reference #8 below (in Portuguese).

That’s what I learned in school !


1: USB4 Specification merges Thunderbolt 3 and USB with transfer speeds up to 40 Gb/s

2: RS-232

3: RS-422

4: RS-485

5: USB

6: IEEE 1394

7: Thunderbolt

8: Frente segura

*: What did you learn in school today ?

2016-06-25 (Lördag)

Idag lärde jag mig, att:

Det finns ett bevingat uttryck om att alla har rätt till sina 15 minuter av berömdhet. Exakt varifrån det kommer är inte helt klart, men bl.a. sägs den amerikanske konstnären Andy Warhol ha varit inblandad.

I alla fall, just idag för exakt två år hade min tur kommit, och jag måste ha gjort något extra fint, för jag förärades med övertid, 16 minuter! Mitt under brinnande fotbolls-VM så blev jag intervjuad om mitt liv och situationen i Brasilien av Sveriges Radio Jämtland. Om du blev nyfiken nu, så kan du se mer och höra intervjun i referens nummer 1 nedan.

Dagens huvudfoto togs 2014-06-09 i São Paulo, där en frukt- och grönsaksstormarknad hyllade de portugisiska och japanska kolonierna i Brasilien i samband med VM. Här följer ytterligare ett foto från samma VM, taget utanför hotellet för Costa Ricas delegation i Santos:

Costa Rica

Costas Ricas delegation tränade i Santos under VM. Denna bild, från 2014-06-20, togs på entrén till deras hotell.

Apropå mat, förmodligen blev det hel del igår, inte sant? I vilket fall som helst, här blir det ännu mer av den varan:

Tycker du om choklad, men är rädd för att få i dig för mycket fett om du äter den? Forskare vid Temple University i Philadelphia, PA, USA, har kommit på ett sätt att minska fettet i choklad med 10 … 20 % genom att under tillverkningsprocessen lägga på ett starkt elektriskt fält. Smaken sägs dessutom vara underbar och framhäva kakaons kvaliteter. Om allt går väl så kan sådan choklad dyka upp i affärerna redan om ett år. Mer om detta i referens nummer 2 nedan.

Men mat kan också inspirera snabbmatsleverantörer till unika reklamkampanjer. KFC (ex-Kentucky Fried Chicken) och Pizza Hut har under den senaste tiden haft dessa intressanta idéer, se också referenser 3-6 nedan, med videoklipp från kampanjerna:


Fyra intressanta matrelaterade kampanjer. I övre raden, från vänster till höger: Ett Bluetooth tangentbord som kommunicerar med en smartphone, från KFC i Tyskland; och Nagellack med kycklingsmak, från KFC i Hong Kong. I nedre raden, från vänster till höger: En kycklinglåda med inbyggd batteriladdare, från KFC i Indien; och slutligen En filmprojektor, från Pizza Hut i Hong Kong.

Slutligen, den kärva ekonomin, kombinerad med torrt väder, har lett till att en fundamental ingrediens i de brasilianska maträtterna, bönor, har försvunnit från mataffärernas hyllor. Detta föranledde följande teckning i Folha de S. Paulo:


“Men mamma, vart har bönorna tagit vägen ?” “Jag sålde dem för att kunna köpa middagsmat.” Teckning av Benett i Folha de S. Paulo, 2016-06-23

… Tack för idag, slut för idag!

(This all-Swedish post deals with an interview by Radio Sweden with yours truly during FIFA World Cup in 2014, and various items of food.)


1: Stefan Johansson berättar om livet som svensk brasilianare under VM

2: Chocolate makers cut fat with electricity

3: KFC’s Tray Typer keeps you clicking even with greasy fingers

4: KFC-flavored nail polish gives new meaning to ‘chicken fingers’

5: Charge your phone with KFC’s new take-out box

6: This pizza box doubles as a movie projector

+: What did you learn in school today ?

2016-04-05 (Tuesday)

Today, I learned that:

In a world with so much violence, crimes and frauds, one could expect that at least sport competitions would give us some time to recover our senses and enjoy them.

But unfortunately, there is so much mischief going on also in sports, that it further adds on to all the other stress items we have to endure.

This morning, I read in Folha de S. Paulo, see reference #1 below, that the government of the State of São Paulo, for safety reasons, will not permit that the supporters of the away team in the matches among the teams from the capital, the so-called “classical matches”, be present in the stadium. The drop that made the bottle flow over was the violence last Sunday, in connection with the match between Palmeiras and Corinthians. A person waiting for his bus home at a bus stop was shot and died. He had nothing to do with the fighting supporters, just happened to be “at the wrong place at the wrong time”.

In Sweden, the premium football league, named “Allsvenskan” started the 2016 season last Sunday. The public attendence was good, even higher than the icehockey games of Swedish Hockey League, but there is one thing that I find most distressing in relation to the so-called “supporters” who find more pleasure in lighting artifical fires, “Bengal fires” on the grandstands, instead of concentrating themselves on the game. How about arranging separate competitions between Bengal supporters instead, who can create the finest, multi-coloured, smoky fires, so that real football fans can watch their game without the incendiary disturbance? If you are literate in Swedish, listen also to the interview in reference # 2, where the police give their negative opinion about this practice.


Supporters from IFK Göteborg “enjoying” their Bengal fires, in an earlier game against IF Elfsborg. Photo by Björn Larsson Rosvall / TT

… That’s what I learned in school !


1: Governo impõe torcida única para clássicos em São Paulo

2: Polisen ser ingen lösning på bengalerna

+: What did you learn in school today ?

2016-01-26 (Tuesday)

Today, I learned that:

The custom of numbering the houses on a street, in order to facilitate visits, delivery of mail and parcels, etc., is said to have started in 1512, when there was built a new bridge in Paris, Pont Notre-Dame. On the bridge were built 68 equal houses and in order to distinguish one from another, they were given golden numbers on the outside, with odd numbers on one side and even numbers on the other side of the bridge. Initially, the purpose of this numbering was not so much to find the house for a visit, but sort of registration of property.

Pont Notre-Dame

La Joute des mariniers entre le Pont-Notre-Dame et le Pont-au-Change, painted by Nicolas-Jean-Baptiste Raguenet in 1752.

Today, practically all towns and cities have a numbering system, although there are differences. The article in Wikipedia, referenced below, deals with the numbering in most parts of the world, so I will not repeat it, but recommend it if you are interested in knowing further details. Here, I will only give some bullet points and also complement that article with some interesting pieces of information.

The basic rule is that the numbering starts in some place with high importance to the city, e.g. City hall, Main cathedral, etc. So the point of the street that is closest to this reference point receives the lowest number and the numbering then increases when you move away from the reference point. It is also very common that one side of the street, normally the left side, receives odd numbers and the other (right) side gets even numbers, just like in Paris in 1512. However, there are exceptions, where the odd numbers are used on the right side and even numbers on the left side.

The distribution of the numbers can be either sequential or by distance. The traditional, sequential distribution, such as 1, 3, 5, 7, 9, 11, … only indicates the relative position of a certain building compared to the reference point and other buildings on the same side of the street, but does not necessarily include information about the distances involved. This type of distribution is prevalent in Europe and many of its former colonies.

However, a different number distribution is very common in USA and Canada. It is basically the same as for sequential distribution, but usually all numbers are not present. The increase in the number used on a building, when compared to its neighbour located closer to the reference point, signifies roughly the distance (in yards) between the two. This distribution system goes hand in hand with the distribution of houses in blocks, and where each new block starts with a multiple of 100. Of course this means that it is easier to know how big is the distance still to be covered to the desired building, merely subtracting one number from the other.

Yesterday, I wrote about São Paulo, and since Brazil is not covered in this Wikipedia article, let me complement it with some information also from Brazil. The predominant system here is similar to the one used in North America, except that the distance is measured in meters, since Brazil uses the SI system. However, there are some Brazilian cities that use the sequential distribution, e.g. Santos, which celebrates its birthday today, being founded on January 26, 1546. However, the 8-year younger city, São Paulo, uses the distribution by distance, where most of the streets rely on Praça da Sé, the city center, as the reference point. However, in the Southern Zone of São Paulo, that until 1935 was the autonomous city of Santo Amaro, the numbering starts at the Cathedral of Santo Amaro.

… That’s what I learned in school!


1: House numbering

+: What did you learn in school today ?

2016-01-25 (Monday)

Today, I learned that:

There may still be hope for humanity. Even if there is big doubt if we will be able to slow down the global warming sufficiently, at least it seems that we are starting to take control over the growth in population. Let me start my reasoning in São Paulo, the biggest city in South America:

São Paulo celebrates it 462nd anniversary today with a local holiday. It was founded on January 25, 1554, under the name of São Paulo dos Campos de Piratininga, by a college of twelve Portuguese jesuit priests, the most well known being Manuel da Nóbrega and José de Anchieta. In 1560, It was renamed Vila de São Paulo, belonging to the Captaincy of São Vicente, whose main village was Brazil’s first one, founded in 1532. The coming centuries did not contribute much to history, but in 1711 São Paulo was converted from town to city. However, there were still few people living in the city. In 1872, there is an information that the population amounted to only 31.385 inhabitants. But from that point on has been a steep slope upward, with the current official number being 11.316.149 inhabitants (2011), and an estimate from the national statistics agency IBGE of 11.967.825 inhabitants in 2015.

In order for us to see the evolution of São Paulo from a village to one of the biggest cities in the world, let us look at the following table, which compares the growth of the population of São Paulo and the entirely world:


As you can see, the current population growth rates are the lowest recorded during the last two centuries, so I believe it is a good sign that the world population will be able to take care of itself for quite some time yet.


Avenida Paulista, São Paulo, October 14, 1990

Returning to São Paulo, where I lived during 19 years old, and where both of my children were born: What can be more typical than characterizing them as “paulistas” (from the state of São Paulo), “paulistanos” (from the city of São Paulo), born on the biggest street Avenida Paulista (which also serves as a background to the photo above of my parents, taken in 1990), and, hopefully, also “são paulinos” (fans of São Paulo Football Club).

Finally, today is also the birthday of my sister-in-law Sônia, お誕生日おめでとう!

… That’s what I learned in school.


1: São Paulo on Wikipedia

2: São Paulo no IBGE

3: Population growth

4: World population

5: São Paulo FC

+: What did you learn in school today ?