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Things I never want to see on a Raspberry Pi

Posted: Mon Apr 18, 2016 3:13 am
by Douglas6
1. A blue LED
2. Windows Desktop
3. Candy Crush Saga
4. Flash
5. Kitten videos
6 Thumbprint detection
7. Piezo speaker
8. 64 GB of RAM
9. FireWire
10. COBOL

Re: Things I never want to see on a Raspberry Pi

Posted: Mon Apr 18, 2016 3:46 am
by mathboy4life
Whats wrong with a blue led?

Re: Things I never want to see on a Raspberry Pi

Posted: Mon Apr 18, 2016 4:06 am
by stderr
mathboy4life wrote:Whats wrong with a blue led?
Reminds him too much of Kmart.

Re: Things I never want to see on a Raspberry Pi

Posted: Mon Apr 18, 2016 4:15 am
by W. H. Heydt
Douglas6 wrote: 10. COBOL

Code: Select all

[email protected] ~ $ apt-cache search cobol
open-cobol - COBOL compiler
It's in the Jessie repositories.

Re: Things I never want to see on a Raspberry Pi

Posted: Mon Apr 18, 2016 4:19 am
by Douglas6
Deleted

Re: Things I never want to see on a Raspberry Pi

Posted: Mon Apr 18, 2016 4:20 am
by Douglas6
W. H. Heydt wrote:
Douglas6 wrote: 10. COBOL

Code: Select all

[email protected] ~ $ apt-cache search cobol
open-cobol - COBOL compiler
It's in the Jessie repositories.
Yeah, I know, and I was a COBOL programmer in the early eighties. On a Pi; it's just not right.

Re: Things I never want to see on a Raspberry Pi

Posted: Mon Apr 18, 2016 5:58 am
by Goraxium
Douglas6 wrote:1. A blue LED
2. Windows Desktop
3. Candy Crush Saga
4. Flash
5. Kitten videos
6 Thumbprint detection
7. Piezo speaker
8. 64 GB of RAM
9. FireWire
10. COBOL
1. Blue LEDs tend to draw more power. There would be no benefit in switching to them.

2. There's a push for this. Not entirely sure why. The only reason why I still use a windows computer is for a few select tasks (primarily ripping CDs, since I don't have an external drive). Otherwise it just gathers dust (especially since my phone does most of what I used my computer for in the past).

3. With the push by a select few to get Android running on the Pi, it'll happen eventually. It doesn't mean you have to play it.

4. Flash is dying... Slowly... It had a good run though...

5. What's wrong with kittens?

6. Thumbprint detection could be a cool little security system project, combined with an RFID reader, voice analysis and retinal scan...

7. There are little speakers in some project kits. I couldn't see one being added to a Pi unless it was for a specific project though.

8. If the Pi continues on for a number of years, and assuming ram continues the trend of cramming more storage into less space, 64GB of ram could potentially be the new baseline at some point. For your average project, it's unnecessary, but as old technology is phased out, it gets harder and harder to cling to it. I remember when 1MB sticks of ram were great, but you'll have issues finding them outside of museums these days.

9. Firewire isn't inherently bad. It does have niche uses though, so without a massive uptake (not likely, with USB 3.0 being the new hotness), it's unlikely to be added without again, being a part of a very specific project.

10. You don't have to use it. The only time I even venture near Java these days, is when I'm using Javascript in Google's script editor. You use what you have to, to get the project done.

Re: Things I never want to see on a Raspberry Pi

Posted: Mon Apr 18, 2016 6:45 am
by ejolson
Goraxium wrote:4. Flash is dying... Slowly... It had a good run though...
Maybe flash refers to having on-board flash memory, which is definitely harder to remove if it needs to be read in another device.
Goraxium wrote:9. Firewire isn't inherently bad. It does have niche uses though, so without a massive uptake (not likely, with USB 3.0 being the new hotness), it's unlikely to be added without again, being a part of a very specific project.
A few years ago I would have been quite excited about a Pi with FireWire as it would allow building a super cheap device for recording and wirelessly streaming DV and HDV video from semi-pro camcorders compared to current products which are 20 to 100 times more costly and either not programmable or much bigger.

For me DRM (digital rights management) software and hardware is the thing I would prefer not ever becoming part of the Pi. In particular, an educational platform designed for people to tinker with and learn programming should not contain hardware and software that is illegal (in some countries) to tinker with.

Re: Things I never want to see on a Raspberry Pi

Posted: Mon Apr 18, 2016 6:47 am
by Pithagoros
Android.
It's Linux + cruft and in my opinion a pit of malevolence that makes MS and Windows look like a paragon of virtue.

Re: Things I never want to see on a Raspberry Pi

Posted: Mon Apr 18, 2016 6:54 am
by Heater
Goraxium,

Blue LEDs tend to draw more power.

Citation/link please.

As far as I can tell a milliamp though a series LED/resistor consumes the same power no matter what colour the LED is.

With today's highly efficient LEDs there should be no need to drive noticeably more current through a blue as a red.

There would be no benefit in switching to them.
True. Except for the colour blind perhaps.

Re: Things I never want to see on a Raspberry Pi

Posted: Mon Apr 18, 2016 7:10 am
by Jednorozec
Goraxium wrote:5. What's wrong with kittens?
The trouble with a kitten is that
Eventually it becomes a cat.
- Ogden Nash

Re: Things I never want to see on a Raspberry Pi

Posted: Mon Apr 18, 2016 7:14 am
by gregeric
Heater wrote:As far as I can tell a milliamp though a series LED/resistor consumes the same power no matter what colour the LED is.
Voltage drop differs among the available colours, as I dare say does efficiency.

Re: Things I never want to see on a Raspberry Pi

Posted: Mon Apr 18, 2016 7:17 am
by Heater
I'm a afraid the human race has a very bad cat infestation.

Cats were probably useful and OK when they spent most of the time outside hunting rats and mice. Mine used to like to leave half a dead mouse, with it's entrails hanging out, on the front door step in the morning after a night out hunting to show me what a good cat it was.

Problem is cats today spend all their time living in luxury indoors, looking out the window, consuming food and internet bandwidth, for no useful purpose.

Re: Things I never want to see on a Raspberry Pi

Posted: Mon Apr 18, 2016 7:38 am
by Heater
gregeric,
Voltage drop differs among the available colours
Yes it does.

But you are always going to have a resistor in series with your LED, that resistor is dissipating power as well. The voltage used to drive the series LED/resistor will always be the same. Only the value of the resistor need change to vary the current to adjust for any difference in efficiency between colours.

As it happens a table on this page: http://deltas.blog.com/2013/06/05/blue- ... ellow/blue indicates that blue can be more efficient. 5ma vs 10 or 20 for similar luminous intensity.

Code: Select all

Colour                       Green      Red	    Yellow	Blue	     White
Operational Forward Current	 20	        10	    10	    5	         5	        mA
Luminous Intensity	         14.5 – 57	16 – 50	10 – 50	11.5 – 28.5  45 – 90	mcd
Of course this all depends on your perception and taste. My point was that there is not any huge difference in power consumption that it's worth worrying about.

Re: Things I never want to see on a Raspberry Pi

Posted: Mon Apr 18, 2016 9:30 am
by jamesh
Blue LED's are better because they are blue.

Re: Things I never want to see on a Raspberry Pi

Posted: Mon Apr 18, 2016 10:27 am
by blaablaaguy
jamesh wrote:Blue LED's are better because they are blue.
Yeah, what he said.
And why not 64gigs of ram? The more the better

Re: Things I never want to see on a Raspberry Pi

Posted: Mon Apr 18, 2016 10:30 am
by hippy
Douglas6 wrote:64 GB of RAM
That might well become a baseline need in future.

Some say we should be encouraging programmers coming into the game to code more efficiently but in practice it's even more "Import this" and job done, not one care or thought for how much unnecessary bloat comes with that, these days than it ever was.

I am not saying that's entirely wrong, but the price we have to accept for ease of development and doing more in code is needing ever increasing amounts of memory.

Re: Things I never want to see on a Raspberry Pi

Posted: Mon Apr 18, 2016 7:17 pm
by stderr
jamesh wrote:Blue LED's are better because they are blue.
As long as they aren't flashing and super bright, my beaglebone blacks put on a light show. I also just found a usb cable with a blue light in it that is steady compared to the super bright red flashing insane one I was using. I put electrical tape over it and the light still got out!

I noticed that at least the LED stop lights around here seem to have the same number of diodes for the red and for the green but because, I guess, our eyes are more sensitive to green, the green light is much brighter than the red one. I think that is a design flaw.

Re: Things I never want to see on a Raspberry Pi

Posted: Mon Apr 18, 2016 7:27 pm
by mahjongg
blue LEDs have a forward voltage of near 3.0V, which means that from a 3.3V source you need a very small ohmic value resistor to get the required current, which reduces the choices you have, also any variation in the 3V3 supply will cause visible brightness changes, so blue LED's are actually not a good idea. As are white LEDs, which are actually blue LEDs with some yellow phosphors to get yellow light. that is why the have exactly the same current needs (which is very dependent on the LED type, you can't just say they "need 5mA")

But to feed a Blue LED exactly 5mA from a 3V3 source you would theoretically need a 60 Ohm resistor, your practical choice is thus reduced to 56 Ohm 62 ohm or 68 ohm. or two 120 ohm resistors in parallel.

Re: Things I never want to see on a Raspberry Pi

Posted: Mon Apr 18, 2016 8:14 pm
by edo1
jamesh wrote:Blue LED's are worse because they are blue.
agreed

Re: Things I never want to see on a Raspberry Pi

Posted: Mon Apr 18, 2016 8:16 pm
by Dutch_Master
The E96 range has 60 available :P

In any case, the RPi BCM chip (whichever one it is) may run on 3V3, it's still powered from a 5V USB port. Use an open collector pin and it doesn't matter anymore which voltage the LED is connected to. Replacing the "power on" led with an RGB one would be a nice feature, as it might simplify error diagnosis. Various colours and whether or not it's blinking and in what frequency can all indicate a specific fault during boot and/or operations.

Re: Things I never want to see on a Raspberry Pi

Posted: Wed Apr 20, 2016 4:20 pm
by Grindipo
jamesh wrote:Blue LED's are better because they are blue.
Blue LED's are more agressive to my eyes.

Re: Things I never want to see on a Raspberry Pi

Posted: Wed Apr 20, 2016 9:05 pm
by Heater
Ultra Violet LEDs are even better. They are even more blue :)

Re: Things I never want to see on a Raspberry Pi

Posted: Wed Apr 20, 2016 9:11 pm
by Tzarls
Pithagoros wrote:Android.
It's Linux + cruft and in my opinion a pit of malevolence that makes MS and Windows look like a paragon of virtue.
Why? Really, I'm curious about why you dislike Android so much.

Re: Things I never want to see on a Raspberry Pi

Posted: Wed Apr 20, 2016 9:17 pm
by JRV
Heater wrote:I'm a afraid the human race has a very bad cat infestation.

Cats were probably useful and OK when they spent most of the time outside hunting rats and mice. Mine used to like to leave half a dead mouse, with it's entrails hanging out, on the front door step in the morning after a night out hunting to show me what a good cat it was.

Problem is cats today spend all their time living in luxury indoors, looking out the window, consuming food and internet bandwidth, for no useful purpose.
20 years ago we had a mouse problem so we got a cat. No more mice in the house. When my daughter said we should get another cat my answer was "Why? I don't have a bow or a mandolin."