[PD] Sensors GPIO Raspberry Pi Pd
Julian Brooks
jbeezez at gmail.com
Fri Apr 19 20:51:10 CEST 2013
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
>> UNSUBSCRIBE and account-management -> http://lists.puredata.info/**
>> listinfo/pd-list <http://lists.puredata.info/listinfo/pd-list>
>>
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.puredata.info/pipermail/pd-list/attachments/20130419/3d075850/attachment.htm>
More information about the Pd-list
mailing list