[PD] Sensors GPIO Raspberry Pi Pd

Julian Brooks jbeezez at gmail.com
Fri Apr 19 22:54:06 CEST 2013


hmmm - both files:
./hello-2
Segmentation fault

Try again...



On 19 April 2013 21:51, Julian Brooks <jbeezez at gmail.com> wrote:

> Ok -found I had to remove 'libi2c-dev'.
>
> Then builds.
>
> More soon...
>
>
> On 19 April 2013 21:28, Julian Brooks <jbeezez at gmail.com> wrote:
>
>> Hey Martin,
>>
>> When I try to compile hello.c I get:
>> gcc -o hello hello.c
>> In file included from hello.c:8:0:
>> /usr/include/linux/i2c-dev.h:38:8: error: redefinition of 'struct i2c_msg'
>> /usr/include/linux/i2c.h:67:8: note: originally defined here
>> /usr/include/linux/i2c-dev.h:90:7: error: redefinition of 'union
>> i2c_smbus_data'
>> /usr/include/linux/i2c.h:125:7: note: originally defined here
>>
>> Dunno if this is at all relevant but maybe this is a good time to say I
>> have a rev1 RPi so I'm on i2c 0 not 1.
>> The Pi install is very up to date though, including recent runs of
>> hexxeh's 'rpi-update' tool so all the system's fresh.
>>
>> I did attempt to change the number of bytes to be read which perhaps
>> would explain why the .h file's are complaining but I don't understand it
>> for your version which is 'as-is'?
>>
>> In fact why don't I attach the notes I've made of the changes to the c
>> file you sent.  Was vaguely hoping I might be able to say 'ta da' but have
>> fallen at the 1st fence:( bugger.
>>
>> Julian
>>
>>
>>
>>
>>
>> On 19 April 2013 19:51, Julian Brooks <jbeezez at gmail.com> wrote:
>>
>>> Hi Martin,
>>>
>>> Meant to add re setting baud rate:
>>> I've been making use of the gpio utility that comes with wiringPi
>>> https://projects.drogon.net/raspberry-pi/wiringpi/the-gpio-utility/
>>> Very handy for getting a quick visualisation of the current state of all
>>> the pins and also easy-access to setting the baud rate too (amongst other
>>> stuff).
>>>
>>> Julian
>>>
>>>
>>> On 19 April 2013 14:36, Martin Peach <martin.peach at sympatico.ca> wrote:
>>>
>>>> Hi Julian,
>>>> Yes I've been messing with coding it in c on the pi and sending the
>>>> data to a [netreceive] in a Pd patch on another machine. I'm attaching the
>>>> source code for the pi part and the Pd patch.
>>>> The code can be compiled on the pi with
>>>> gcc -o hello hello.c
>>>> You need to set the IP address of the receiving machine in the code (I
>>>> have 192.168.2.15, it could be 127.0.0.1 for the same machine).
>>>> I tried changing the baud rate with
>>>> sudo modprobe -r i2c_bcm2708
>>>> sudo modprobe i2c)bcn2708 baudrate=90000
>>>> but it works fine at the default 100000.
>>>> It seems that you only need to write the command once, after that
>>>> simply reading gets you another packet. Using a combined write/read
>>>> operation only works half the time, as I also found on the Arduino. All you
>>>> need to do is write the 0x4C command once, wait a millisecond or so and
>>>> then read it.
>>>> Another issue is that I tried this with the 8X1 sensor, not the 4X4
>>>> one, so the code reads 19 bytes (need to change the expected read size in
>>>> the code). The 4X4 sensor sends 35 bytes which is 3 more than the i2c
>>>> driver maximum, so you may not get the last part of a packet.
>>>> I'll try it later with a 4X4 sensor to see what happens.
>>>>
>>>> Martin
>>>>
>>>>
>>>> On 2013-04-19 07:01, Julian Brooks wrote:
>>>>
>>>>> Hi Martin,
>>>>>
>>>>> Did you manage to make any progress with the sensor on the Pi?
>>>>> I also wanted to ask whether the output we're receiving from i2cdump
>>>>> makes any sense to you as it doesn't to us currently?  Tried searching
>>>>> around for possible info on the 'XX' & 'ff' but drawing a blank here.
>>>>>
>>>>> Cheers,
>>>>>
>>>>> Julian
>>>>>
>>>>>
>>>>> On 13 April 2013 01:11, Julian Brooks <jbeezez at gmail.com
>>>>> <mailto:jbeezez at gmail.com>> wrote:
>>>>>
>>>>>     Hey all,
>>>>>
>>>>>     Some success finally:
>>>>>
>>>>>     Hurrah!!
>>>>>
>>>>>     The scl breakout pin on the pi proto plate wasn't working properly.
>>>>>
>>>>>     When unscrewed halfway it works, when fully screwed in it doesn't.
>>>>>
>>>>>     So - now got this:
>>>>>
>>>>>     i2cdetect -y 0
>>>>>
>>>>>     0 1 2 3 4 5 6 7 8 9 a b c d e f
>>>>>
>>>>>     00: -- -- -- -- -- -- -- 0a -- -- -- -- --
>>>>>
>>>>>     10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
>>>>>
>>>>>     20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
>>>>>
>>>>>     30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
>>>>>
>>>>>     40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
>>>>>
>>>>>     50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
>>>>>
>>>>>     60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
>>>>>
>>>>>     70: -- -- -- -- -- -- -- --
>>>>>
>>>>>     and
>>>>>
>>>>>     i2cdump -y 0 0xa
>>>>>     No size specified (using byte-data access)
>>>>>
>>>>>     Gives a whole host of stuff I don't yet understand but I don't care
>>>>>     currently as something is actually happening.
>>>>>
>>>>>     Will figure out a way of saving the console info (any hints
>>>>>     anyone?)  as it gets badly mangled when cutting and pasting  but
>>>>>     basically something like this:
>>>>>
>>>>>     i2cdump -y 0 0xa
>>>>>     No size specified (using byte-data access)
>>>>>           0  1  2  3  4  5  6  7  8  9  a  b  c  d  e
>>>>>     f                      0123456789abcdef
>>>>>     00: ff XX XX XX XX XX XX ff XX XX XX XX ff ff ff XX
>>>>>  .XXXXXX.XXXX...X
>>>>>     10: XX ff XX XX XX XX XX ff XX ff XX ff XX XX ff XX
>>>>>  X.XXXXX.X.X.XX.X
>>>>>     20: ff XX XX ff XX XX ff XX XX XX XX ff XX XX XX ff
>>>>>  .XX.XX.XXXX.XXX.
>>>>>     30: XX ff XX ff XX XX XX XX ff ff ff XX XX XX XX XX
>>>>>  X.X.XXXX...XXXXX
>>>>>     40: XX XX XX ff XX ff XX XX XX 64 XX XX d5 XX XX ff
>>>>>  XXX.X.XXXdXX?XX.
>>>>>     50: XX ff XX XX XX XX XX XX XX ff XX XX ff XX XX XX
>>>>>  X.XXXXXXX.XX.XXX
>>>>>     60: ff XX XX XX ff XX XX XX XX XX XX XX XX ff XX XX
>>>>>  .XXX.XXXXXXXX.XX
>>>>>     70: XX XX XX XX XX XX XX ff XX XX XX XX XX XX XX XX
>>>>>  XXXXXXX.XXXXXXXX
>>>>>     80: XX ff XX XX ff ff XX XX XX ff XX XX XX XX XX XX
>>>>>  X.XX..XXX.XXXXXX
>>>>>     90: XX XX ff XX XX ff XX ff XX ff ff XX XX ff ff XX
>>>>>  XX.XX.X.X..XX..X
>>>>>     a0: XX ff XX XX ff XX XX XX XX XX XX XX XX XX ff XX
>>>>>  X.XX.XXXXXXXXX.X
>>>>>     b0: XX XX ff XX XX XX ff XX XX ff XX XX XX XX XX XX
>>>>>  XX.XXX.XX.XXXXXX
>>>>>     c0: XX XX XX XX ff XX XX ff ff XX XX ff ff XX XX XX
>>>>>  XXXX.XX..XX..XXX
>>>>>     d0: XX XX XX XX XX ff XX ff XX XX XX XX XX ff XX ff
>>>>>  XXXXX.X.XXXXX.X.
>>>>>     e0: XX XX XX ff XX ff XX XX XX XX XX XX XX XX ff XX
>>>>>  XXX.X.XXXXXXXX.X
>>>>>     f0: ff XX ff ff XX XX XX XX XX XX XX XX XX XX ff XX
>>>>>  .X..XXXXXXXXXX.X
>>>>>
>>>>>
>>>>>     Progress at least.
>>>>>
>>>>>     Cheers,
>>>>>
>>>>>     Julian
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>     On 12 April 2013 11:27, Julian Brooks <jbeezez at gmail.com
>>>>>     <mailto:jbeezez at gmail.com>> wrote:
>>>>>
>>>>>         Message resent for thread archives with smaller picture size.
>>>>>
>>>>>         Julian
>>>>>
>>>>>         ---------- Forwarded message ----------
>>>>>         From: *Julian Brooks* <jbeezez at gmail.com <mailto:
>>>>> jbeezez at gmail.com>>
>>>>>         Date: 11 April 2013 19:24
>>>>>         Subject: Re: [PD] Sensors GPIO Raspberry Pi Pd
>>>>>         To: Martin Peach <martin.peach at sympatico.ca
>>>>>         <mailto:martin.peach@**sympatico.ca<martin.peach at sympatico.ca>
>>>>> >>
>>>>>         Cc: PD List <pd-list at iem.at <mailto:pd-list at iem.at>>
>>>>>
>>>>>
>>>>>         Hey Martin / list,
>>>>>
>>>>>         Finally got all the stuff and ...
>>>>>
>>>>>         It’s not working!
>>>>>
>>>>>         We spent the day soldering cables and connecting stuff up as
>>>>> per
>>>>>         the Omron ‘App Note 01’ spec sheet.
>>>>>
>>>>>         Started off super-conservative using the  I2C level converter
>>>>>         (case 3 page 4) http://www.adafruit.com/**
>>>>> products/757#Blog/Flickr<http://www.adafruit.com/products/757#Blog/Flickr>
>>>>>
>>>>>         We tried resistors on both sides (being super paranoid!) and
>>>>>         then we took  the low (Pi) side ones off.
>>>>>
>>>>>         We then moved on to case 2 page 3 of this same document…
>>>>>
>>>>>         At each stage we checked with “I2Cdetect –Y 1” and nothing was
>>>>>         visible.
>>>>>
>>>>>         The grid shows no attached devices every time we run it.
>>>>>
>>>>>         We re-booted at every stage following the various online
>>>>>         tutorials/methods of setting up I2C GPIO on the Pi (checked &
>>>>>         double checked).
>>>>>
>>>>>
>>>>>         As you can see we’re using a pi protoplate:
>>>>>
>>>>>         https://www.adafruit.com/**products/801<https://www.adafruit.com/products/801>
>>>>>
>>>>>         In the photo I’ve attached the cables are coded as follows:
>>>>>
>>>>>         Orange           GND
>>>>>
>>>>>         Yellow            5v
>>>>>
>>>>>         Blue                SCL
>>>>>
>>>>>         Green             SDA
>>>>>
>>>>>         The white is also 5v for the pull up resistors.
>>>>>
>>>>>         The resistor values are 4.7k btw.
>>>>>
>>>>>         We have tested the cable that terminates at the sensor and all
>>>>>         that is OK.
>>>>>
>>>>>         I put a multimeter on the GND and SDA solder points on the
>>>>>         sensor itself and got 3.7v…
>>>>>
>>>>>         I put a multimeter on the GND and SCL solder points on the
>>>>>         sensor itself and got 0.0v…
>>>>>
>>>>>         Don’t know if this means anything or could be useful to know!
>>>>>
>>>>>         Stuck and frustrated now but hey, 3 weeks ago I knew absolutely
>>>>>         bugger all about any of this and now I do (sort of).
>>>>>
>>>>>         I'm thinking we could do with the most basic i2c sensor we can
>>>>>         find as we have nothing to compare.
>>>>>
>>>>>         Tonight I'm going to d/l a fresh raspbian and start from
>>>>> scratch
>>>>>         to check that end.
>>>>>
>>>>>         Feel like if we can't get past the 'i2c-tools' tests we're
>>>>>         screwed - never mind getting it in and out of Pd.
>>>>>
>>>>>         Any thoughts/pointers/options from anyone will be really
>>>>>         appreciated?
>>>>>
>>>>>
>>>>>         Cheers,
>>>>>
>>>>>
>>>>>         Julian
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> ______________________________**_________________
>>>>> Pd-list at iem.at mailing list
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>>>>>
>>>>>
>>>>
>>>
>>
>
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