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by ejfield
Thu Jun 16, 2016 7:59 am
Forum: Advanced users
Topic: What is MySQL doing?
Replies: 7
Views: 2102

Re: What is MySQL doing?

Thanks for all your replies. You all seem to be confirming what I suspected, that MySQL is probably doing some housekeeping in the background, which could be causing the corruption on power-off. Firstly, a controlled shut-down is not an option. As I mentioned, the system is headless, and the user ha...
by ejfield
Fri Jun 10, 2016 8:33 am
Forum: Advanced users
Topic: What is MySQL doing?
Replies: 7
Views: 2102

What is MySQL doing?

I have a system based on a RPi, which runs, amongst other things, Apache and MySQL. The Web Server front end collects data and writes it into the MySQL database (relatively infrequently). A compiled 'C' program runs in an infinite loop in the background, reading the data out of the MySQL database. A...
by ejfield
Thu May 01, 2014 5:40 pm
Forum: Advanced users
Topic: Mounting USB Memory
Replies: 9
Views: 1799

Re: Mounting USB Memory

ghans wrote:Can't you assign several UUIDs on the same mountpoint ?

ghans
Well I could, if I knew the UUID of every USB stick I'm ever likely to use. Unfortunately, I dont.
by ejfield
Thu May 01, 2014 10:04 am
Forum: Advanced users
Topic: Mounting USB Memory
Replies: 9
Views: 1799

Re: Mounting USB Memory

Curiouser and curiouser ... why? What happens if, when you format the sticks, you give them the same 'label', and use that? (And perhaps use the label as the "mount point name" too). Trev. Well, I want to be able to plug in any USB stick containing my data, and expect to find it at the same mount p...
by ejfield
Wed Apr 30, 2014 7:25 pm
Forum: Advanced users
Topic: Mounting USB Memory
Replies: 9
Views: 1799

Re: Mounting USB Memory

ghans: I cant use UUIDs because I want to be able to mount different USB sticks at the same mount point. Tarcas: Thanks for that clarification, but what determines which device name is used? Normally, I wouldn't have thought a USB stick, formatted at FAT32 I think, would contain any partitions, so I...
by ejfield
Wed Apr 30, 2014 7:17 am
Forum: Advanced users
Topic: Mounting USB Memory
Replies: 9
Views: 1799

Mounting USB Memory

It's possible I'm going mad, but I seem to be having odd things happening when I mount a USB memory stick. Typically, I plug the stick in, and look at it's device name with "df -h". This is USUALLY either "/dev/sda", or "/dev/sda1". I havn't worked out what the difference between them is, or why som...
by ejfield
Tue Mar 19, 2013 8:26 am
Forum: Python
Topic: goAgain?
Replies: 12
Views: 1528

Re: goAgain?

Try this: password = "password" attempt = "" while attempt != password : attempt = input("Enter password: ") print ("Incorrect Password") print( "Correct Password") Note that the two print statements are in Python3 format - you will probably want to remove the brackets. ...and raw_input changed to i...
by ejfield
Mon Mar 18, 2013 3:41 pm
Forum: Python
Topic: WiringPython - from the beginning
Replies: 6
Views: 1453

Re: WiringPython - from the beginning

Thanks for the useful input, particularly the link to the benchmarks. For some reason I had got the idea that WiringPi was faster than GPIO/RPIO, neither of which is anything like fast enough for my application. I'd got rather hung-up on Python, probably because it's (relatively) easy to use and (co...
by ejfield
Sun Mar 17, 2013 9:29 am
Forum: Python
Topic: WiringPython - from the beginning
Replies: 6
Views: 1453

WiringPython - from the beginning

Hello all you helpful clever people! There is a lengthy thread on WiringPython elsewhere, but I got a bit lost wading through it, some of the links are broken, other bits are a bit confusing (to me anyway), so I thought it best to start a new thread. I (think) I want to try using Wiring Python, as a...
by ejfield
Sat Mar 09, 2013 9:17 pm
Forum: Python
Topic: RPIO: An extension of RPi.GPIO with interrupts, PWM and more
Replies: 84
Views: 21464

Re: RPIO: An extension of RPi.GPIO with interrupt management

That's fixed it! Thanks a lot.

regards
Ed
by ejfield
Sat Mar 09, 2013 8:53 pm
Forum: Python
Topic: RPIO: An extension of RPi.GPIO with interrupts, PWM and more
Replies: 84
Views: 21464

Re: RPIO: An extension of RPi.GPIO with interrupt management

Hmm, good point, I didn't think of that.

I installed with:
$ sudo apt-get install python-setuptools
$ sudo easy_install -U RPIO

I havn't tried python2. Any idea how to install RPIO for python3?
by ejfield
Sat Mar 09, 2013 6:40 pm
Forum: Python
Topic: RPIO: An extension of RPi.GPIO with interrupts, PWM and more
Replies: 84
Views: 21464

Re: RPIO: An extension of RPi.GPIO with interrupt management

I thought I'd try using RPIO instead of GPIO, but I'm having trouble. It installed OK, I replaced "import RPi.GPIO as GPIO" with "import RPIO as GPIO", as suggested, but when I run my python(3) script, I just get "ImportError: No module named RPIO".

Any suggestions?
by ejfield
Thu Nov 15, 2012 12:46 pm
Forum: HATs and other add-ons
Topic: Gertboard Software in Python - Released
Replies: 80
Views: 24403

Re: Gertboard Software in Python - Released

Yup that seems to work. I was slightly confused at first sight though, so here's a suggestion. If the only codes for rev1 are 0002 and 0003, why not set the default for boardRev to 2 (instead of -1), then you only need the test for 0002 and 0003, which will set boardRev to 1.

cheers.
by ejfield
Tue Nov 13, 2012 10:32 pm
Forum: HATs and other add-ons
Topic: Gertboard Software in Python - Released
Replies: 80
Views: 24403

Re: Gertboard Software in Python - Released

Yes I think it will be hex, a quick google suggests that a few other values are kicking about. And yes it failed as you suggested - something like "invalid literal for int with base 10", which seem fair!

Keep up the good work.
by ejfield
Tue Nov 13, 2012 5:40 pm
Forum: HATs and other add-ons
Topic: Gertboard Software in Python - Released
Replies: 80
Views: 24403

Re: Gertboard Software in Python - Released

You've probably found this already, but my recent 512Mb rev 2 board has the revision ID "000f", which doesn't parse well with int(line[-5:-1]) !!
by ejfield
Mon Oct 22, 2012 8:33 am
Forum: HATs and other add-ons
Topic: Pi reboots when 3.3v jumper is placed?
Replies: 7
Views: 2648

Re: Pi reboots when 3.3v jumper is placed?

When you say it reboots, does it reboot with the jumper still on, or only when you remove the jumper? If it's the former, it's unlikely to be a short, since this would take down the 3v3 permanently. In this case, it could be that the inrush current to the gertboard is causing a brown-out on the 3v3 ...
by ejfield
Fri Oct 19, 2012 10:38 am
Forum: HATs and other add-ons
Topic: Gertboard parts list
Replies: 10
Views: 5308

Re: Gertboard parts list

Thanks, that was very useful. I think there's a minor typo in the first item - the part number should be 175-9265 for the 100nF SMD caps.

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