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by timrowledge
Tue Sep 17, 2019 11:11 pm
Forum: Scratch
Topic: Raspberry Pi 4 and Scratch 2
Replies: 6
Views: 515

Re: Raspberry Pi 4 and Scratch 2

:-)
by timrowledge
Tue Sep 17, 2019 6:33 pm
Forum: Beginners
Topic: Computer monitor & Raspberry Pi 4B
Replies: 5
Views: 167

Re: Computer monitor & Raspberry Pi 4B

Simpler to use VNC. No cable to buy.
Use the Pi preferences tool to enable VNC.
Install RealVNC on your Mac.
Done.
It’s been working perfectly for me (with minor variations over the years) since ‘13.
by timrowledge
Thu Sep 12, 2019 8:43 pm
Forum: Scratch
Topic: Raspberry Pi 4 and Scratch 2
Replies: 6
Views: 515

Re: Raspberry Pi 4 and Scratch 2

Just out of interest because I don’t have a pi4 yet, does my ‘original ‘ Scratch run ok? It should but proof is always good.
by timrowledge
Wed Aug 21, 2019 6:02 pm
Forum: General discussion
Topic: Uses for Raspberry Pi Zero/Zero W?
Replies: 81
Views: 2835

Re: Uses for Raspberry Pi Zero/Zero W?

Not so very long ago a machine with the performance of a Pi zero was a thing of fantasy, affordable only for high end engineering workstations.
by timrowledge
Tue Aug 20, 2019 6:24 pm
Forum: Off topic discussion
Topic: double cpu's
Replies: 15
Views: 2991

Re: double cpu's

A 384 Core Cavium ThunderX 2 machine would be quite fast, but I fear the cost might put you off. Last time i looked we were talking $24000 without t ram and disks.
On the other hand the BitScope stuff could provide a 160 core Pi 4 based machine with plenty of ram and disc for less than $6k.
by timrowledge
Fri Aug 09, 2019 8:50 pm
Forum: General discussion
Topic: Using PiServer with Pi 4
Replies: 9
Views: 562

Re: Using PiServer with Pi 4

If you want to save time it might be worth getting a few 3B+ to do your experiments. They do usb and pxe boot and since time is (often) money in business...
by timrowledge
Thu Aug 01, 2019 6:21 pm
Forum: Off topic discussion
Topic: Before Raspberry Pi
Replies: 14
Views: 3378

Re: Before Raspberry Pi

It's even better. That 4Mz 8080 was probably running at 1 MIPs or so. The Pi 4 is more like 1 GIP. And it has 4 cores. 4000 times faster! 8080 was probably more like 0.5mips in practice. A72 ARM is multi-issue, out of order so much more than 1gip; likely 1.5 at least. And, obviously, at least 4 x t...
by timrowledge
Sat Jul 27, 2019 9:05 pm
Forum: General discussion
Topic: Raspberry pi for coding on machine level?
Replies: 31
Views: 1379

Re: Raspberry pi for coding on machine level?

Unless you’re planning on writing a code generator there really isn’t much reason to worry about the very lowest level type of programming. I’ve done a fair bit whilst creating dynamic code translation systems for x86/68k/alpha/spark/arm/hp7000/etc and to be honest it makes for a fairly unpleasant t...
by timrowledge
Tue Jul 23, 2019 8:00 pm
Forum: General programming discussion
Topic: ESC Direction
Replies: 6
Views: 1237

Re: ESC Direction

PeterO wrote:
Mon Jul 22, 2019 6:15 pm
Model boat ESC's are also normally reversible.
PeterO
Good point. I imagine at least some of them are water cooled as well, which could be fun for a car; an excuse for a radiator!
by timrowledge
Mon Jul 22, 2019 6:09 pm
Forum: General programming discussion
Topic: ESC Direction
Replies: 6
Views: 1237

Re: ESC Direction

Very few R/C plane ESCs provide reverse, so unless OP is using a car type ESC it is unlikely to be possible to get reversing.
by timrowledge
Sat Jul 20, 2019 3:40 pm
Forum: General programming discussion
Topic: Liberation through Computer Literacy
Replies: 1125
Views: 50952

Re: Project Digital Apocalypse Not Now

I just took advantage of the nice tweak gkriedel spotted and was pleased to see that it improved the calculation time for the big fib from circa 6secs to circa 4.8. Printing time, obviously, wasn’t changed. Your 30 second experience was not when using Squeak on an intel machine unless it is a 486 er...
by timrowledge
Fri Jul 19, 2019 5:12 am
Forum: General programming discussion
Topic: Liberation through Computer Literacy
Replies: 1125
Views: 50952

Re: A Final Fibonacci Challenge

gkreidl wrote:
Wed Jun 26, 2019 6:09 pm
Taking out the check for 0 is a good idea. My Python function now looks like this:
{snip}
Nice! That gets the calculation time for Squeak on my Pi3b+ to ~4.5sec. A clear and simple improvement from the ~6secs of the prior version.
by timrowledge
Mon Jul 15, 2019 5:37 pm
Forum: General discussion
Topic: Usefull / good programs to have on your Pi
Replies: 22
Views: 1494

Re: Usefull / good programs to have on your Pi

Botspot wrote:
Mon Jul 15, 2019 4:58 pm
And my Windows 10 transformation pack (Makes Raspbian Pixel look and feel like Windows 10)
What, deliberately? Why? Whyyyyyyyyyyyyyy!
by timrowledge
Wed Jul 10, 2019 1:15 am
Forum: General programming discussion
Topic: GUI Editor Code Challenge
Replies: 174
Views: 5054

Re: GUI Editor Code Challenge

Oh dear.i can’t offer any submission for Smalltalk - after all it’s already had a nice graphical editor with nice fonts and menus since the PARC team invented them.
And no, Heater, GNU Smalltalk not included.
by timrowledge
Mon Jul 01, 2019 8:49 pm
Forum: General discussion
Topic: I Need More Meat From My Pi
Replies: 12
Views: 758

Re: I Need More Meat From My Pi

As for #5 - write better code! Have you run profiling on it? Have you worked out where the time is going? Have you evaluated your algorithms for effectiveness? What about compiler flags? It’s rare to not be able to at least double performance over a first version. Better algorithms can provide order...
by timrowledge
Mon Jul 01, 2019 8:45 pm
Forum: General discussion
Topic: Raspberry Pi 4 usb boot?
Replies: 303
Views: 51811

Re: Raspberry Pi 4 usb boot?

hardwaremack-orginal wrote:
Mon Jul 01, 2019 6:02 pm
I'm not trying to offend anyone, just stating reality. booting and operating from a SD card is playing with fire.
Really? Are you unaware of how many millions of Pi have been working entirely adequately from SD cards for the last 6years or so?
by timrowledge
Wed Jun 19, 2019 7:35 pm
Forum: Beginners
Topic: Power on / shutdown RPI time or network
Replies: 7
Views: 400

Re: Power on / shutdown RPI time or network

There are HATs and other units that can shut a Pi down and remove power, and start it up again when a button is pressed. But I don't know of any that include a timer option. At least a couple have RTCs and micro controllers on board. The piups hat appears to be one example. SparkFun etc carry them.
by timrowledge
Wed Jun 19, 2019 7:21 pm
Forum: General discussion
Topic: How can I connect a lot of Gear flow sensor sensors to RPI?
Replies: 3
Views: 235

Re: How can I connect a lot of Gear flow sensor sensors to RPI?

Take a look at using an ESP8266 per keg, each connected to one sensor. ESPs are really cheap ($5) and are essentially very fast Arduino’s with built-in WiFi. The advantages here are that the Arduino approach handles the real-time interrupt stuff well and the WiFi means easy use of MQTT to send your ...
by timrowledge
Mon Jun 17, 2019 4:13 pm
Forum: General discussion
Topic: Generate multiple PWM signals
Replies: 5
Views: 329

Re: Generate multiple PWM signals

Consider a pwm HAT - SparkFun and AdaFruit both do good pca9685 units. Drive via i2c commands from joan’s Piggpio or even my own daemon.
by timrowledge
Sun Jun 16, 2019 8:04 pm
Forum: Scratch
Topic: Scratch 1.4 audio lock-up after raspbian update && upgrade
Replies: 2
Views: 1786

Re: Scratch 1.4 audio lock-up after raspbian update && upgrade

I've racked my brain trying to work out what might be happening here but had no success. The fact that reinstalling 'fixes' it adds confusion. NuScratch does absolutely nothing strange with sounds; it uses ALSA for sound output through the normal device criving api for unix. ALSA does have a bit of ...
by timrowledge
Sat Jun 15, 2019 4:21 pm
Forum: Off topic discussion
Topic: Motors required for rc car
Replies: 2
Views: 1203

Re: Motors required for rc car

Go to rcgroups.com and look down the list of forums for the car stuff (lots of plane and boat fun as well). You’ll find people doing pretty much anything you can imagine.
by timrowledge
Thu Jun 06, 2019 6:19 pm
Forum: General programming discussion
Topic: I wants LOLcodes!
Replies: 38
Views: 2051

Re: I wants LOLcodes!

I’d say it is a pretty good mickey-take of the strained syntax that so many people consider ‘normal’ for programming.
by timrowledge
Tue Jun 04, 2019 7:59 pm
Forum: General programming discussion
Topic: Liberation through Computer Literacy
Replies: 1125
Views: 50952

Re: A Final Fibonacci Challenge

Evidently we were talking at cross purposes for a long time as I struggled to get a result out of Smalltalk. Evidently. It happens. It's whart we invented words for though, right? I just wanted to do a simple thing. Run a program that took a single integer parameter in and put a single integer resu...
by timrowledge
Tue Jun 04, 2019 5:54 pm
Forum: General programming discussion
Topic: Liberation through Computer Literacy
Replies: 1125
Views: 50952

Re: A Final Fibonacci Challenge

There's a place for "no talking" libraries. But I also believe there's a place for "scream your head off and bounce from the walls" libraries if that is what people want and it helps them advance. Exactly. There's plenty of grump old gits like me & Heater; kids and other less jaundiced folk have a ...
by timrowledge
Tue Jun 04, 2019 5:52 pm
Forum: General programming discussion
Topic: Liberation through Computer Literacy
Replies: 1125
Views: 50952

Re: A Final Fibonacci Challenge

timrowledge, Wait, hang on - how does using any sort of approximation via a floating point number produce a correct answer to an integer problem? Surely that can't be right? Magic isn't it! Damn right. I'm not a Numerics guy by any stretch but that really make my head spin. I'll see what my mathema...

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