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by bulletmark
Sat Jan 03, 2015 1:09 pm
Forum: HATs and other add-ons
Topic: Powering issue via Piface Digital
Replies: 1
Views: 480

Re: Powering issue via Piface Digital

Can't really help except to say that I powered my RPi + PiFace Digital board + wifi adaptor from a single 5V supply connected to the PiFace board without any issues for about 1 year. Make sure JP3 is connected properly, see http://www.element14.com/community/servlet/JiveServlet/previewBody/53057-102...
by bulletmark
Sat Jan 03, 2015 1:00 pm
Forum: Bare metal, Assembly language
Topic: Bare Metal SPI
Replies: 7
Views: 3551

Re: Bare Metal SPI

Is there any reason you want to avoiding using the python interface to the PiFace board?
by bulletmark
Sun Dec 07, 2014 12:58 pm
Forum: HATs and other add-ons
Topic: old PIRs and PiFace
Replies: 5
Views: 1952

Re: old PIRs and PiFace

Also, without any information about the PiFace board (see my other posts for my opinion of PiFace) it's difficult to know if there's any pull-up on its input, and without that there wouldn't be any voltage on the emitter. The PiFace digital board enables it's MCP23S17 pull-up resistors by default o...
by bulletmark
Sun Dec 07, 2014 2:40 am
Forum: HATs and other add-ons
Topic: old PIRs and PiFace
Replies: 5
Views: 1952

Re: old PIRs and PiFace

I should clarify this given you mention you have little electronics experience. The PIR NC contact pair is called a "dry-contact". It is driven by a relay output on the PIR and doesn't provide any voltage or power. It is normally closed when no movement is detected and 12v power is applied to the PI...
by bulletmark
Sun Dec 07, 2014 1:55 am
Forum: HATs and other add-ons
Topic: old PIRs and PiFace
Replies: 5
Views: 1952

Re: old PIRs and PiFace

I have a few different types of PIRs in my home but all have the same 4 pins: +/- 12V for operation, and one NC contact pair for the alarm input. So I just wired the NC contacts into the PiFace input and ground and that is it. No need for anything special. I have had the 6 PIRs (plus 2 other contact...
by bulletmark
Thu Oct 30, 2014 11:17 pm
Forum: Beginners
Topic: Keep output status in piface after restart
Replies: 3
Views: 546

Re: Keep output status in piface after restart

ste73 wrote:Godo idea, any example? :)
Here's a simple program which polls the 8 piface inputs (including the 4 switches) and toggles the outputs on or off if the input is toggled on. It saves the states in a file so it can resume the same outputs after system restart.
by bulletmark
Thu Oct 30, 2014 1:07 pm
Forum: Beginners
Topic: Keep output status in piface after restart
Replies: 3
Views: 546

Re: Keep output status in piface after restart

Your program writes the state of each output relay. So are you asking how your program can keep it's state over a reboot? Store state in a file then read that at boot and write the piface outputs.
by bulletmark
Tue Oct 28, 2014 10:52 pm
Forum: C/C++
Topic: C++, Code::Blocks, MS SQL SERVER
Replies: 8
Views: 6078

Re: C++, Code::Blocks, MS SQL SERVER

I'm actually "Skinning the same cat" but from the other direction. I have a Raspberry Pi with a PiFace card that is logging contact closure pulse rates on several inputs (using Python) which is saved to a local log file on the RPi. Then I have my SQL Server running a scheduled task to regularly gra...
by bulletmark
Thu Oct 16, 2014 1:57 am
Forum: Troubleshooting
Topic: PI Face Not Detected
Replies: 13
Views: 6124

Re: PI Face Not Detected

Check that jumpers JP1 and JP2 are set correctly for board 0 address. See http://www.farnell.com/datasheets/1684425.pdf.
by bulletmark
Wed Oct 15, 2014 8:41 am
Forum: Troubleshooting
Topic: PI Face Not Detected
Replies: 13
Views: 6124

Re: PI Face Not Detected

diana1990 wrote:I tried using code of bulletmark but nothing changed :/
You "tried using code". What does that mean? Did you type the commands exactly as I listed in my first post above? Did you get any error messages? If so, then please state them (exactly) here. Nobody can help unless the problem is clear.
by bulletmark
Tue Sep 16, 2014 11:14 pm
Forum: HATs and other add-ons
Topic: Adafruit 2.8" PITFT stopped the PIFACE I/O card
Replies: 5
Views: 1957

Re: Adafruit 2.8" PITFT stopped the PIFACE I/O card

The RPi does have 2 separate chip selects for the SPI though. Not sure about this but perhaps you could route the SPI_CE0 header pin from the PiFace board to SPI_CE1? Refer http://2.bp.blogspot.com/-O8fqpxHsuFQ/UhXwZzNJT7I/AAAAAAAAIVw/jhAsMoB2Ssg/s1600/Pi-face-digital-schematic.png. Would have to ch...
by bulletmark
Mon Aug 25, 2014 1:02 pm
Forum: Python
Topic: problem with piface digital io
Replies: 2
Views: 1233

Re: problem with piface digital io

metso wrote:I guess the input read function needs some time to recover before the next one should be applied.
That should not be the case. Post your complete code here and I will attempt to correct it for you.
by bulletmark
Wed Aug 20, 2014 10:59 pm
Forum: HATs and other add-ons
Topic: Can you make PiFace hold state after deinit() and init()?
Replies: 1
Views: 545

Re: Can you make PiFace hold state after deinit() and init()

You could use my alternative piface board python interface at https://github.com/bulletmark/pifaceio.

If you use the piface module compatability api [i.e. init()/deinit()] etc then of course it will reset all outputs in the init() just like the original module but my native api does not do that.
by bulletmark
Sat Jul 19, 2014 2:33 pm
Forum: Python
Topic: Pifacedigital coding
Replies: 2
Views: 1047

Re: Pifacedigital coding

piface is the old/original python module for the piface board and is now considered obsolete, pifacedigitalio is the new python module. Regarding your second question, I can't thing of an easy way to use a Android voice command, perhaps use the app Autovoice with Tasker, or send an sms/email. but pe...
by bulletmark
Mon Jul 14, 2014 1:48 am
Forum: Beginners
Topic: beginners Tutorials and kids learning
Replies: 4
Views: 984

Re: beginners Tutorials and kids learning

The official web site is pretty good, e.g.: http://www.piface.org.uk/guides/Install ... al_Python/
by bulletmark
Tue Jul 01, 2014 9:46 am
Forum: HATs and other add-ons
Topic: PiFace HC-SR04
Replies: 11
Views: 2720

Re: PiFace HC-SR04

The external device drives the line low. What do you base that statement on? Here's schematic for the HC-SR04 . Looks to me that the ECHO ping is floating so will need an external pull-down resistor. Also, here's another guy on this forum using same chip and he has also added a pull-down resistor.
by bulletmark
Tue Jul 01, 2014 8:52 am
Forum: HATs and other add-ons
Topic: PiFace HC-SR04
Replies: 11
Views: 2720

Re: PiFace HC-SR04

ame wrote: Why would you do that? What you want is a floating input that can be driven high or low by the external device. Pull-ups or -downs are not necessary.
Think about the state when 5V is not applied. It needs to be pulled low to make sure the input does not float randomly.
by bulletmark
Tue Jul 01, 2014 8:39 am
Forum: HATs and other add-ons
Topic: PiFace HC-SR04
Replies: 11
Views: 2720

Re: PiFace HC-SR04

Try turning off the pullup on the input you are using. I am not a hardware expect but the PiFace board pulls each input high by default (using the internal chip resistors to internal 5V source) and you turn an input ON by asserting it active low to ground. So if you want to do the opposite of this ...
by bulletmark
Thu Jun 26, 2014 10:31 pm
Forum: Beginners
Topic: Gertboard vs PiFace vs RasPiComm
Replies: 3
Views: 1260

Re: Gertboard vs PiFace vs RasPiComm

PiFace gives you real world control and sensing, 2 relays associated to 2 outputs and 4 buttons connected to 4 inputs; Piface actually provides 8 screw terminal N/O inputs, and 8 screw terminal O/C outputs. It is the same size as the RPi and snaps neatly on top of it. The 4 buttons provided are in ...
by bulletmark
Mon May 19, 2014 10:42 pm
Forum: Graphics, sound and multimedia
Topic: jukebox issue [Errno 2]
Replies: 1
Views: 774

Re: jukebox issue [Errno 2]

No one has replied so I will throw in a suggestion to try. Add "shell=True" argument to your Popen().
by bulletmark
Thu May 15, 2014 10:28 pm
Forum: Python
Topic: running python programs
Replies: 3
Views: 839

Re: running python programs

If you install pifacedigitalio following it's instructions you don't need root to run any programs.
by bulletmark
Sun May 11, 2014 9:51 am
Forum: Python
Topic: Piface inputs
Replies: 1
Views: 514

Re: Piface inputs

Your requirements are unclear. Do you really want each output pin just to reflect the state of each input pin? So when you release the pin the output turns off immediately? If so then see the first example on my pifaceio page. Or, as I suspect, do you want to press + release an input which sets the ...
by bulletmark
Sat May 10, 2014 11:33 pm
Forum: Python
Topic: PiFace digital, problem outputs
Replies: 1
Views: 551

Re: PiFace digital, problem outputs

Changing the second "pf.init()" to "pf.init(init_board=False)" is the answer you think you are looking for.
by bulletmark
Thu May 01, 2014 5:03 am
Forum: Beginners
Topic: Piface input voltage terminals
Replies: 2
Views: 531

Re: Piface input voltage terminals

There have been two PiFace board hardware versions released, Mk 1 and Mk 2. E.g. I don't think the Mk 1 version had 8 leds on the output, and other minor changes. They are identical from a software perspective.
by bulletmark
Sat Apr 26, 2014 10:22 pm
Forum: Python
Topic: Pi Face
Replies: 23
Views: 3944

Re: Pi Face

could I modify the script be to say the following Of course you can change the code to do anything. if button is pressed 1 time within 5 seconds connect relay for 2 seconds, but if button/input is pressed 5 times in 5 seconds connect relay for 10 seconds. Sounds easy, but it means you will have a 5...

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