jecel

14 ms·

121.
by jecel 3y ago
Normally education or human oriented languages start arrays at 1 (Smalltalk, Cobol, Lua, APL, Wolfram, etc) while hardware oriented languages start arrays at 0 (C and friends, Oberon, Forth, Scheme and so on). Human oriented languages that
122.
by jecel 3y ago
"Seventy five years ago, the University’s ‘Baby’ computer became the first electronic computer with a read/write memory to run a program." says the article. The modified ENIAC used a kind of ROM for its program (a function ta
123.
by jecel 3y ago
> The idea of Carrier Sense is that the "carrier" signal on the network indicates that the network is idle. Wouldn't a carrier indicate that the network is busy? Actually, Ethernet is a baseband system and so doesn't
124.
by jecel 3y ago
While friction is invariant with the area, adhesion is proportional to the area. Tire grip is much more adhesion (think a glue-like chemical reaction) than friction, which is why race cars use such wide tires even though that ruins the air
125.
by jecel 3y ago
The original motivation for the Pi was to offer current generations the same learning opportunities that low cost home computers offered those growing up in the 1980s. An expensive shared family PC in the 2000s didn't encourage tinkeri
126.
by jecel 3y ago
There is a design style called RTL (register transfer level) which works better with registers that have separate clock and enable inputs. The clock goes to all registers, but on any given cycle only a subset of those are enabled depending
127.
by jecel 3y ago
About 20 years ago I was watching the local news (small town in Brazil) and one of the things they showed was a farmer's 130th birthday. He had been bedridden for nearly a year at that point but everyone commented how he had been still
128.
by jecel 3y ago
IBM simply followed the tradition created by the companies already in the microcomputer market. Apple's documentation, for example, included the full schematics and the source listing for the ROMs: http://cini.classiccmp.org
129.
by jecel 3y ago
I should also have mentioned The Mill architecture as an example of dealing with code as blocks of instructions instead of each one separately. In this case they get a higher fetch rate for their VLIW machine by starting execution from the
130.
by jecel 3y ago
We are still moving forward and hope to have interesting things to show soon. For any other readers, my Morphle Engine (aka SiliconSqueak 5) processor design has many elements in common with EDGE (and so with Dataflow as well). I found the
131.
by jecel 3y ago
I have twice had the experience of meeting a professor who had done their PhD in the late 1980s/early 1990s on Dataflow and were lamenting having wasted their time since it turned out to be a dead end. I pointed out to them that the co
132.
by jecel 3y ago
Small correction: MOS Technology was an already existing company known for its calculator chips when Peddle took his team from Motorola to work there. A very interesting recentish example was Andreas Olofsson leaving Analog Devices in 2008
133.
by jecel 3y ago
Tesla invented this because he wasn't happy that cavitation was reducing the life of bladed turbines.
134.
by jecel 3y ago
You can have a compiler or assembler in a Harvard Architecture computer, but having separate instruction and data memories means that you can't generate the instructions and then execute them. You need some scheme to move stuff from on
135.
by jecel 3y ago
There is a Walmart Supercenter close to where West Palmetto Park crosses US 441. I don't know it that is outside the city limits.
136.
by jecel 3y ago
Great blog post. Some observations: Ada was not originally an object-oriented language, though it eventually became so. But the 432 project predated Ada and pivoted to that language when it came out. Intel had to adapt Ada to work with obje
137.
by jecel 3y ago
It is funny to see VME boards considered "large" (though there were options to allow them to be huge). The name is "VersaModules European format" replacing the 370x230mm VersaBus boards with 233.35x160mm 6U for typical V
138.
by jecel 3y ago
It was a joke: when Seymour was informed that Apple was using a Cray machine to design their computers he said something like "funny, I use an Apple computer to design the Cray". But in reality he never used computers at all but d
139.
by jecel 3y ago
Both Cuis and Squeak (from which both Pharo and Cuis were forked) are still actively developed. Pharo does have the largest presence in the two major Smalltalk conferences (FAST in Argentina and ESUG in Europe) but there is no need to worry
140.
by jecel 3y ago
Here is a recent discussion: https://millcomputing.com/topic/what-is-your-roadmap-for-202...
141.
by jecel 4y ago
Having watched hundreds of academic presentations and been at many technical conferences, I don't agree. If you compare a paper published in a conference's proceedings with the corresponding oral presentation (which is what his vi
142.
by jecel 4y ago
The 286 added "in string" and "out string" instructions. It turned out that if peripherals had a small internal buffer it was more efficient to use these new instructions instead of using DMA hardware. This is why hard d
143.
by jecel 4y ago
In some equipment, like the Teletype Model 33[1], you had left arrow and up arrow instead of _ and ^. This was part of the 1963 draft of ASCII, but was changed in the final version. In the early 1980s there was still a lot of equipment by D
144.
by jecel 4y ago
Reversible computing[1] allows us to use less energy than the von Neumann–Landauer limit of kT ln(2) energy dissipated per irreversible bit operation (note that our current technology is still many orders of magnitude from this limit). It d
145.
by jecel 4y ago
"The 68000 uses much wider microcode (85-bit microinstructions compared to 21 bits in the 8086)." is not what I remembered. Another source says "The actual internal representation is a combination of "microcode" and
146.
by jecel 4y ago
The TMS340 family used bit addresses, but pointers were 32 bits. https://en.wikipedia.org/wiki/TMS34010
147.
by jecel 4y ago
I saw one of those running Cromix. It was being sold in Brazil as if it were a local machine by Brascom called BR-1000[1]. They called the OS "BR1000" as well. Some students were trying some examples from the manual and they weren
148.
by jecel 4y ago
The Alto could emulate different instruction sets via microcode (like their previous machine emulated a PDP-10) and it came with a built in emulation for the Data General Nova, but internally it was a very different machine. The biggest sim
149.
by jecel 4y ago
I think you are both right. The term "killer app" can be used for something that causes people to buy something else no matter how expensive just to have that first thing. Visicalc for the Apple II, Lotus 123 for the IBM PC and cl
150.
by jecel 4y ago
See the October 5 1960 entry in this list: https://en.wikipedia.org/wiki/List_of_nuclear_close_calls

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