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Comment Because it's terrible (Score 1) 413

This is often because in-car tech is terrible. The user interfaces often seem to be reminiscent of something knocked together for Windows CE in the mid 90s, they are often awkward and laggy and counterintuitive. And basically they are ossified to the car's manufacture date, and you have to pay through the nose for data updates. When I last changed my car, the car was 18 years old - would an in-car satnav/other tech still be supported 18 years after it came out?

All I want in a car today is this: some USB charging ports, some point on the vehicle interior that allows you to attach a tablet or phone holder, and a decent Bluetooth implementation. It's far easier to update my phone or tablet than anything actually built into a car, and I can also take it with me and use it in a rental vehicle, on my bicycle, in my house etc.

Comment Re:"In recent years" ? (Score 1) 242

It's not unique to programming. It's everywhere. Good looking young fresh faces sell newspapers and magazines, the older face of experience does not. For instance, take music - predominantly young acts are promoted, and older acts that are making new music that's arguably better are ignored. See the headline "21 year old entrepreneur starts X business" - but never see the headline "50 year old entrepreneur starts X business" etc. The obsession with youth is human nature, not something unique to the computer world.

Comment Re:Assholes! (Score 1) 188

They are probably not messing with the cell service, it's probably that there are so many people hitting the same cell tower that you're just running out of bandwidth.

I've seen it happen at Event City in Manchester, the quality of your cell connection is inversely proportional to the amount of people attending.

Comment Re:Are they going to fine airlines for doing the s (Score 1) 188

They interfere with small aircraft avionics too, I've seen it (on an instrument approach, in the rain, at night). GSM is particularly obnoxious, it's pretty much guaranteed to wipe out all the audio and has a high chance of causing course deviation indicators to deflect.

We were intercepting the localiser one night and suddenly, all the audio was obliterated by "bip b b bip b b bip b b bip b b bip bRRRRRRRRRRRRRRRRRRRRRRRRRR" as my friend's wife called him. If ATC had given us an instruction at that moment we would not have heard it. It was also extremely distracting.

Comment Re:Needless limiting of options (Score 1) 170

What's most inaccurate is that he says that using a MOSFET means always a really simple circuit with the microcontroller directly connected to the gate of the MOSFET and nothing else in the circuit (except the pulldown resistor). In Microcontroller And MOSFETs 101 you soon learn about inductive loads and the problems they can cause, relays are the popular example - when you turn off the current to the relay you get a big voltage spike over the MOSFET. This capacitatively couples over the gate and zaps the output pin of the microcontroller, usually causing it to crash, but it can also cause the output to latch up and destroy the microcontroller. You need some circuitry to prevent this, usually a diode across the relay and a resistor in series with the gate, but he mentions none of this.

Comment Re: The 555 timer sucks. (Score 1) 170

Maybe not a microcontroller, but a whole circuit.

Before high power LED bike lights were commercialized, I made a daylight visible rear light for my bike after I got rear ended, using 6 x 1 watt red Luxeon LEDs. I wanted it to flash a pattern so it would show up in a driver's vision, but for night time use I wanted it to be less bright and be a steady light. While the 555 timer is very very cheap and a PWM circuit for dimming the LEDs and flashing them could easily be made, an ATtiny13 turned out to be a cheaper way to implement the circuit because instead of potentiometers to control brightness, very cheap pushbuttons could be used to cycle through the program running on the microcontroller.

A 555 timer costs pennies, and an ATtiny13 costs about 50p (about US $0.75). Pushbuttons cost pennies, potentiometers cost pounds.

Comment Re:Where are the advantages? (Score 1) 170

There are also some pitfalls of MOSFETs he should really mention (probably why people are using these old BJT power transistors is they are a bit more forgiving in this respect). When driving motors and relays, you often get some inductive 'kick', and this will capacitatively couple across the MOSFET's gate and go right back to the microcontroller's pin. Usually this results in just the microcontroller crashing, but it may also result in latch-up which can quickly destroy the microcontroller (I've seen it happen).

It can normally be prevented with a diode across the relay and a 10k resistor to the gate of the MOSFET (which will slow its turn on time, but usually we don't care all that much for these applications) but the original article mentions none of this and you'd have thought the author would have known better!

"Don't try to outweird me, three-eyes. I get stranger things than you free with my breakfast cereal." - Zaphod Beeblebrox in "Hithiker's Guide to the Galaxy"