mmoskal

14 ms·

181.
by mmoskal 4y ago
For example LoRaWAN uses AES-CTR and AES-CMAC. BLE uses AES-CDC. Both are relatively easy to implement on Cortex M0 and up (which start at 10-30 cents).
182.
by mmoskal 4y ago
The reprogrammable 8 bit Padauk PFS122 is around 6 cents, though out of stock. That's less then PY32 though admittedly not by much. https://www.lcsc.com/mobile/product-detail/Microcontroller-U...
183.
by mmoskal 4y ago
TFA says this one isn't STM32 clone though. Just the peripherals are similar. Not sure about ARM license.
184.
by mmoskal 4y ago
It could be an advantage if the rp2040 had a decent low power mode - then you could only turn on the wifi when you need it (eg data upload every few hours) and run for a year on battery. Alas it doesn't... I think the main advantage (t
185.
by mmoskal 4y ago
The article doesn't mention plain ESP32 - the first in family, dual core. These are the most popular on Amazon etc. There is also ESP32-S0WD single core version.
186.
by mmoskal 4y ago
And stop calling machine learning ML while you're at it! It's Meta Language as in OCaml and SML! :)
187.
by mmoskal 4y ago
Legacy? Google public cloud operation is relatively recent.
188.
by mmoskal 4y ago
Right, you can get 100 resistors for (literally) a few cents :)
189.
by mmoskal 4y ago
Still 100x less than a typical US credit card fee.
190.
by mmoskal 4y ago
Interesting to note that there is ~30kWh of energy in a gallon of gasoline, so the reason EV would only take 20% of US electricity consumption is that they are 5x more efficient (than the 20mpg gas figure used). Indeed seems manageable.
191.
by mmoskal 4y ago
Espressif seems to be pulling $180m per year [0], so I guess on the order of 100m devices. The likes of ST and NXP have 10-20x the revenue, but I would venture the majority of what they are selling isn't connected. Nordic revenue was $
192.
by mmoskal 4y ago
Definitely agree on the HAL. I didn't find the ESP32 docs too lacking though (for UART etc; for Wifi/BLE docs are non-existent of course). With STM32 they often have 3+ different kinds of timers (advanced, basic, sometimes also lo
193.
by mmoskal 4y ago
Often only parts of text are pixelated.
194.
by mmoskal 4y ago
It's subsidized. Try getting them at $5 in volume.
195.
by mmoskal 4y ago
Couldn't agree more! One way I was fighting it (in Static Typescript [0]) is by increasing frequency of scans and allocating as close as possible to one side of the heap. Next time I think I'll just try to compact the heap. [0] h
196.
by mmoskal 4y ago
Well yes. The less heap to scan the faster it is. I was just referreing to the unusual ratio between speed and RAM.
197.
by mmoskal 4y ago
Seems to use quite a bit of stack for an embedded usage. An interesting thing to note: microcontrollers are typically memory-bound when using common algorithms - while they are maybe 100x slower than a desktop computer they have say 1000000
198.
by mmoskal 4y ago
I believe 48V would be used since 50V is the maximum voltage considered "safe" for humans. This is also why USB-C goes up to 48V.
199.
by mmoskal 4y ago
I think the gcc tool chain for Xtensa is equally open. It's the binary libraries for wifi and the ROM that are closed.
200.
by mmoskal 4y ago
1-wire is not hard to implement but unfortunately it requires two wires (they never count ground)
201.
by mmoskal 4y ago
So funny, I first read it as six 950, but after the edit comment went back and read 6950 and totally thought the comment got updated in real time.
202.
by mmoskal 4y ago
I've been using a do-it-yourself connector [0] (aka Hack Connect) for my own boards - it stays in the board by itself. Interesting the link you posted - it seems 2x5p 1.27mm version with one pin cut would work as the pogo version of Ha
203.
by mmoskal 4y ago
-fdata-sections can increase code size if you have lots of small global - the compiler doesn't know where they will be placed and has to generate pointer literals for all of them, in every function that use them (due to function sectio
204.
by mmoskal 4y ago
The way it works is that pointers are represented as themselves, assuming top 15 bits being zero. Doubles are shifted by an offset such that nans land at top 15 bits being zero. So assuming pointers are at most 49 bits you're fine.
205.
by mmoskal 4y ago
I believe they only kill SIM in US for now. Could be they keep it for a year or two more in other places until they adapt to eSIM.
206.
by mmoskal 4y ago
Popular in production = hard to get mostly. Eg you can get STM32G030 and similar at quite normal prices at LCSC (and thus JLCPCB assembly service, highly recommended over hand soldering BTW). OTOH stm32f030 (older and 2x worse in most respe
207.
by mmoskal 4y ago
Full 64 bit would very likely need to be boxed (heap allocated). I assume bigint is not boxed up to 40-something bits and instead stored as NaN[0]. Once you start boxing, the additional few instructions to handle things above 64 bit are pro
208.
by mmoskal 4y ago
At least in TypeScript there are hooks in the game loop that let you write pixels on the screen.
209.
by mmoskal 4y ago
Well, LCSC [0] has microB at around $0.02 [1] and USB-C (16 pin) at $0.05 [2] [0] https://lcsc.com/products/USB-Connectors_369.html [1] https://lcsc.com/product-detail/USB-Connectors_XKB-Connectiv.
210.
by mmoskal 4y ago
Probably under $0.05 difference - but when trying to hit $4 retail every cent matters.

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