Re: [Pharo-users] Pharo things analog reads ?

[Denis Kudriashov]

Hi Steven.

I added I2C support
 to
PharoThings and WiringPi.

Now you can ask the board instance for I2C connection:

i2cConnection := board connectToI2CDevice: 4.


And then read/write data using wiringpi functions like:

i2cConnection readData.
i2cConnection read8BitsAt: 16r32 "register".

i2cConnection writeData: 16rAB.
i2cConnection write8BitsAt: 16r32 "register" data: 16rA5.


Also I added I2CDevice as superclass for simple i2c devices. There is
example of accelerometer ADXL345. Look for details.


Best regards,
Denis


2017-12-19 23:20 GMT+01:00 Steven Costiou :

> hi,
>
> i've tried i2c and added ffi calls in WiringPiLibrary.
>
> *wiringPiI2cSetup: devId*
>
> ^self ffiCall: #(int wiringPiI2CSetup (int devId) )
>
> *readI2C: fd*
>
> ^self ffiCall: #(int wiringPiI2CRead (int fd))
>
> Then the following script is able to read a byte from a connected device
> (i tried with a trinket https://learn.adafruit.com/introducing-trinket/
> introduction):
> 
>
> |lib addr val|
>
> lib := WiringPiLibrary uniqueInstance.
>
> addr := self wiringPiSetupI2C: 4. *“Setup the i2c to the 0x04 address”*
> val := self readI2C: addr. *“Read a byte from the i2c address”*
>
> val inspect
>
> So connecting an Arduino-like device to the raspberry that is configured
> as an i2c slave, Pharo can ask for analog values. I will try tomorrow with
> analog sensors, I will share if i manage to build nice examples.
>
> Seems to be even easier using a special chip: https://learn.adafruit.com/
> reading-a-analog-in-and-controlling-audio-volume-with-
> the-raspberry-pi?view=all
>
> but it uses more pins on the board.
>
> Steven.
>
>
>
> Le 2017-12-17 19:48, Denis Kudriashov a écrit :
>
> Hi Steven
>
> 2017-12-17 12:40 GMT+01:00 Steven Costiou :
>
>> Hi,
>>
>> For what i know, raspberry pi boards cannot read analog sensors (which
>> are the most interesting imo), except by connecting to some kind of bridges
>> or to Arduino boards.
>>
>> In the PharoTHings code i see that there are Arduino classes, and also it
>> is based on wiringpi and wiringpi provides support for i2c which is needed
>> to connect to an Arduino and perform analog reads.
>>
>> I'm exploring the wiringpi doc to see if there is an example for that,
>> but in the meantime, would someone already have an example of analog reads
>> with PharoThings, with working code (even simple) ?
>>
> It is in my todo. I need to build example with temperature sensor. I will
> continue work on it next year.
> Now feel free to contribute to the project.
>
> About Arduino: it is not finished. Problem that I use Mac but serial port
> is not working there (it is required for Firmata)
>
>>
>>
>> Steven.
>>
>

Re: [Pharo-users] Pharo things analog reads ?

[PeterJohn via Pharo-users]

--- Begin Message ---
Hi...Have you tried putting a 0.1uF capacitor from the input to GND?How
quickly are you reading? Are you averaging or decimating?
Also, have you added capacitors for the Aref pin?You may be picking up
spurious signals.



--
Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html

--- End Message ---

Re: [Pharo-users] Pharo things analog reads ?

[Steven Costiou]

I finally bought 2 of those chips, and it works very well. 

A simple file read from Pharo and i get my analog values (although i
don't understand them, but that has nothing to do with the reading). It
is very, very fast. 

Thanks again :) 

Steven. 

Le 2017-12-20 05:20, K K Subbu a écrit :

> On Wednesday 20 December 2017 03:50 AM, Steven Costiou wrote: 
> 
>> So connecting an Arduino-like device to the raspberry that is
>> configured as an i2c slave, Pharo can ask for analog values. I will
>> try tomorrow with analog sensors, I will share if i manage to build
>> nice examples.
>> 
>> Seems to be even easier using a special chip: 
>> https://learn.adafruit.com/reading-a-analog-in-and-controlling-audio-volume-with-the-raspberry-pi?view=all
> 
> An Arduino would be an overkill. Also, there is no need for bitbanging. 
> MCP3008 is are directly supported by the IIO subsystem and its channel data 
> is demuxed in /sys/bus/iio/devices/iio:device
> 
> http://www.jumpnowtek.com/rpi/Using-mcp3008-ADCs-with-Raspberry-Pis.html
> 
> HTH .. Subbu

  

Re: [Pharo-users] Pharo things analog reads ?

[Steven Costiou]

Thanks for the link, also ;) 

Le 2017-12-20 05:20, K K Subbu a écrit :

> On Wednesday 20 December 2017 03:50 AM, Steven Costiou wrote: 
> 
>> So connecting an Arduino-like device to the raspberry that is
>> configured as an i2c slave, Pharo can ask for analog values. I will
>> try tomorrow with analog sensors, I will share if i manage to build
>> nice examples.
>> 
>> Seems to be even easier using a special chip: 
>> https://learn.adafruit.com/reading-a-analog-in-and-controlling-audio-volume-with-the-raspberry-pi?view=all
> 
> An Arduino would be an overkill. Also, there is no need for bitbanging. 
> MCP3008 is are directly supported by the IIO subsystem and its channel data 
> is demuxed in /sys/bus/iio/devices/iio:device
> 
> http://www.jumpnowtek.com/rpi/Using-mcp3008-ADCs-with-Raspberry-Pis.html
> 
> HTH .. Subbu

  

Re: [Pharo-users] Pharo things analog reads ?

[Denis Kudriashov]

Thank's for links. I will look

2017-12-19 23:20 GMT+01:00 Steven Costiou :

> hi,
>
> i've tried i2c and added ffi calls in WiringPiLibrary.
>
> *wiringPiI2cSetup: devId*
>
> ^self ffiCall: #(int wiringPiI2CSetup (int devId) )
>
> *readI2C: fd*
>
> ^self ffiCall: #(int wiringPiI2CRead (int fd))
>
> Then the following script is able to read a byte from a connected device
> (i tried with a trinket https://learn.adafruit.com/introducing-trinket/
> introduction):
> 
>



> |lib addr val|
>
> lib := WiringPiLibrary uniqueInstance.
>
> addr := self wiringPiSetupI2C: 4. *“Setup the i2c to the 0x04 address”*
> val := self readI2C: addr. *“Read a byte from the i2c address”*
>
> val inspect
>
> So connecting an Arduino-like device to the raspberry that is configured
> as an i2c slave, Pharo can ask for analog values. I will try tomorrow with
> analog sensors, I will share if i manage to build nice examples.
>
> Seems to be even easier using a special chip: https://learn.adafruit.com/
> reading-a-analog-in-and-controlling-audio-volume-with-
> the-raspberry-pi?view=all
>
> but it uses more pins on the board.
>
> Steven.
>
>
>
> Le 2017-12-17 19:48, Denis Kudriashov a écrit :
>
> Hi Steven
>
> 2017-12-17 12:40 GMT+01:00 Steven Costiou :
>
>> Hi,
>>
>> For what i know, raspberry pi boards cannot read analog sensors (which
>> are the most interesting imo), except by connecting to some kind of bridges
>> or to Arduino boards.
>>
>> In the PharoTHings code i see that there are Arduino classes, and also it
>> is based on wiringpi and wiringpi provides support for i2c which is needed
>> to connect to an Arduino and perform analog reads.
>>
>> I'm exploring the wiringpi doc to see if there is an example for that,
>> but in the meantime, would someone already have an example of analog reads
>> with PharoThings, with working code (even simple) ?
>>
> It is in my todo. I need to build example with temperature sensor. I will
> continue work on it next year.
> Now feel free to contribute to the project.
>
> About Arduino: it is not finished. Problem that I use Mac but serial port
> is not working there (it is required for Firmata)
>
>>
>>
>> Steven.
>>
>

Re: [Pharo-users] Pharo things analog reads ?

[Steven Costiou]

Yeah i know this exists, but i have none of these and i have plenty of
trinkets, and i need to do analog reads. I2c is interesting anyway, some
devices need it i believe. 

Le 2017-12-20 05:20, K K Subbu a écrit :

> On Wednesday 20 December 2017 03:50 AM, Steven Costiou wrote: 
> 
>> So connecting an Arduino-like device to the raspberry that is
>> configured as an i2c slave, Pharo can ask for analog values. I will
>> try tomorrow with analog sensors, I will share if i manage to build
>> nice examples.
>> 
>> Seems to be even easier using a special chip: 
>> https://learn.adafruit.com/reading-a-analog-in-and-controlling-audio-volume-with-the-raspberry-pi?view=all
> 
> An Arduino would be an overkill. Also, there is no need for bitbanging. 
> MCP3008 is are directly supported by the IIO subsystem and its channel data 
> is demuxed in /sys/bus/iio/devices/iio:device
> 
> http://www.jumpnowtek.com/rpi/Using-mcp3008-ADCs-with-Raspberry-Pis.html
> 
> HTH .. Subbu

  

Re: [Pharo-users] Pharo things analog reads ?

[K K Subbu]

On Wednesday 20 December 2017 03:50 AM, Steven Costiou wrote:

So connecting an Arduino-like device to the raspberry that is
configured as an i2c slave, Pharo can ask for analog values. I will
try tomorrow with analog sensors, I will share if i manage to build
nice examples.

Seems to be even easier using a special chip: 
https://learn.adafruit.com/reading-a-analog-in-and-controlling-audio-volume-with-the-raspberry-pi?view=all


An Arduino would be an overkill. Also, there is no need for bitbanging. 
MCP3008 is are directly supported by the IIO subsystem and its channel 
data is demuxed in /sys/bus/iio/devices/iio:device


http://www.jumpnowtek.com/rpi/Using-mcp3008-ADCs-with-Raspberry-Pis.html

HTH .. Subbu

Re: [Pharo-users] Pharo things analog reads ?

[Steven Costiou]

hi, 

i've tried i2c and added ffi calls in WiringPiLibrary. 

WIRINGPII2CSETUP: DEVID

^self ffiCall: #(int wiringPiI2CSetup (int devId) ) 

READI2C: FD

^self ffiCall: #(int wiringPiI2CRead (int fd)) 

Then the following script is able to read a byte from a connected device
(i tried with a trinket
https://learn.adafruit.com/introducing-trinket/introduction): [1] 

|lib addr val| 

lib := WiringPiLibrary uniqueInstance. 

addr := self wiringPiSetupI2C: 4. _"Setup the i2c to the 0x04 address"_
val := self readI2C: addr. _"Read a byte from the i2c address"_ 

val inspect 

So connecting an Arduino-like device to the raspberry that is configured
as an i2c slave, Pharo can ask for analog values. I will try tomorrow
with analog sensors, I will share if i manage to build nice examples. 

Seems to be even easier using a special chip:
https://learn.adafruit.com/reading-a-analog-in-and-controlling-audio-volume-with-the-raspberry-pi?view=all


but it uses more pins on the board. 

Steven. 

Le 2017-12-17 19:48, Denis Kudriashov a écrit :

> Hi Steven
> 
> 2017-12-17 12:40 GMT+01:00 Steven Costiou :
> 
>> Hi, 
>> 
>> For what i know, raspberry pi boards cannot read analog sensors (which are 
>> the most interesting imo), except by connecting to some kind of bridges or 
>> to Arduino boards. 
>> 
>> In the PharoTHings code i see that there are Arduino classes, and also it is 
>> based on wiringpi and wiringpi provides support for i2c which is needed to 
>> connect to an Arduino and perform analog reads. 
>> 
>> I'm exploring the wiringpi doc to see if there is an example for that, but 
>> in the meantime, would someone already have an example of analog reads with 
>> PharoThings, with working code (even simple) ?
> 
> It is in my todo. I need to build example with temperature sensor. I will 
> continue work on it next year. 
> Now feel free to contribute to the project. 
> 
> About Arduino: it is not finished. Problem that I use Mac but serial port is 
> not working there (it is required for Firmata) 
> 
>> Steven.
 

Links:
--
[1] https://learn.adafruit.com/introducing-trinket/introduction)

Re: [Pharo-users] Pharo things analog reads ?

[Denis Kudriashov]

Hi Steven

2017-12-17 12:40 GMT+01:00 Steven Costiou :

> Hi,
>
> For what i know, raspberry pi boards cannot read analog sensors (which are
> the most interesting imo), except by connecting to some kind of bridges or
> to Arduino boards.
>
> In the PharoTHings code i see that there are Arduino classes, and also it
> is based on wiringpi and wiringpi provides support for i2c which is needed
> to connect to an Arduino and perform analog reads.
>
> I'm exploring the wiringpi doc to see if there is an example for that, but
> in the meantime, would someone already have an example of analog reads with
> PharoThings, with working code (even simple) ?
>
It is in my todo. I need to build example with temperature sensor. I will
continue work on it next year.
Now feel free to contribute to the project.

About Arduino: it is not finished. Problem that I use Mac but serial port
is not working there (it is required for Firmata)

>
>
> Steven.
>

[Pharo-users] Pharo things analog reads ?

[Steven Costiou]

Hi, 

For what i know, raspberry pi boards cannot read analog sensors (which
are the most interesting imo), except by connecting to some kind of
bridges or to Arduino boards. 

In the PharoTHings code i see that there are Arduino classes, and also
it is based on wiringpi and wiringpi provides support for i2c which is
needed to connect to an Arduino and perform analog reads. 

I'm exploring the wiringpi doc to see if there is an example for that,
but in the meantime, would someone already have an example of analog
reads with PharoThings, with working code (even simple) ? 

Steven.