I2C bus on RBC (ATMEGA128) for many sensor

[Flid]

The RBC (ATMEGA128) have one I2C bus at pin 25 (SCL/INT0) PD0 & 26 (SDA/INT1) PD1 and used for the eeprom (24LC256SN)

The I2C bus can address 20 items ( 19 Slaves and 1 Master, the RBC ), It's a good opportunities to add many sensors for our RoboBuilder

Maybe somebody have make one hack in this direction and add many I2C
functionality on Robobuilder

[i-Bot]

Robobuilder has two I2C interfaces, one in hardware with the EEPROM and one in software with the accelerometer connected.

I put connectors where the accelerometer was and connected a remote board with accelerometer and I2C camera from wiimote. This works fine.

[Flid]

Robobuilder has two I2C interfaces, one in hardware with the EEPROM and one in software with the accelerometer connected.

I put connectors where the accelerometer was and connected a remote board with accelerometer and I2C camera from wiimote. This works fine.

How you read or write at the second I2C bus ?

[Flid]

No access in RobobuilderLib.dll

Maybe later in the next release

[l3v3rz]

It would need functionality added to RBC firmware i.e. DCMP as well. It currently talks to accelerometer so its possible. The I2C code looks very time critical in places and very device specific - any idea what sort of an interface would be needed to talk to any device?

Alternatively why not connect devices to the wck bus - this is much easier to connect to and easier to talk to. Hamvid uses wck bus (it steal servo id 30), as does the sound chip, the only problem is making sure the devices don't clash when talking. The Cylon head mod I built does the same and I use a PIC chip to read data off the bus.

[l3v3rz]

Ive had a think and I have started coding this in, so it will be in the next version of DCMP and RobobuilderLib.

The .NET interface looks like this (added to wckMotion class)

public bool I2C_write(int addr, byte[] outbuf)
This will send all the bytes in outbuff to the slave 'addr'

public byte[] I2C_read(int addr, byte[] outbuf, int cnt)
This will send all the bytes in outbuf to the slave 'addr' and then
read 'cnt' bytes from the I2C bus.

So example will look like this to initialise the accelerometer:

Code: Select all

            wckMotion wmt = new wckMotion("COM5", true);

           // acc init
            if (!wmt.I2C_write(0x70, new byte[] { 0x14, 0x03 }))
            {
                Console.WriteLine("I2C test failed");
            }


Still testing the communication out - so should be available in a few days/next week

Edit:
here's an example of reading the accelerometer values

Code: Select all

   wmt.I2C_write(0x70, new byte[] {0x02});

   byte[] ib = wmt.I2C_read (0x71, new byte[] {}, 6);      
   Console.WriteLine("x={0}, y={1}, z={2}",
      wmt.cbyte(ib[1]) ,
      wmt.cbyte(ib[3]),
      wmt.cbyte(ib[5]));


cheers

[i-Bot]

Looking good

There are a few examples here of devices we found useful on Robonova ( compass, speech,..) They may at least give you some idea of the variety.
http://robosavvy.com/Builders/i-Bot/I2CC.zip

Wireless nunchuck, might be fun !

My Robonova and robobuilder are a bit "Toy Story 3" at present, so I probably can't help very much.

[Flid]

Ive had a think and I have started coding this in, so it will be in the next version of DCMP and RobobuilderLib.

The .NET interface looks like this (added to wckMotion class)

public bool I2C_write(int addr, byte[] outbuf)
This will send all the bytes in outbuff to the slave 'addr'

public byte[] I2C_read(int addr, byte[] outbuf, int cnt)
This will send all the bytes in outbuf to the slave 'addr' and then
read 'cnt' bytes from the I2C bus.

So example will look like this to initialise the accelerometer:

Code: Select all

            wckMotion wmt = new wckMotion("COM5", true);

           // acc init
            if (!wmt.I2C_write(0x70, new byte[] { 0x14, 0x03 }))
            {
                Console.WriteLine("I2C test failed");
            }


Still testing the communication out - so should be available in a few days/next week

Edit:
here's an example of reading the accelerometer values

Code: Select all

   wmt.I2C_write(0x70, new byte[] {0x02});

   byte[] ib = wmt.I2C_read (0x71, new byte[] {}, 6);      
   Console.WriteLine("x={0}, y={1}, z={2}",
      wmt.cbyte(ib[1]) ,
      wmt.cbyte(ib[3]),
      wmt.cbyte(ib[5]));


cheers

Very Nice Bravo

[Flid]

Hello l3v3rz,

Where I can download your last realease with I2C of DCMP and RobobuilderLib ?

[l3v3rz]

Please have patience - I do only work on this in my spare time.

I haven't made available as a pre-built release yet, although the source is uploaded if you want to build it yourself. I'm working on a few other items before I create a new release as it requires updates to both robobuilderlib and dcmp.hex.

Have you interfaced any I2C sensors yet ? if so which ones and how about some pictures to show what you're up to.

l3v3rz

[Flid]

Have you interfaced any I2C sensors yet ? if so which ones and how about some pictures to show what you're up to.
l3v3rz

In fact, not yet

Not yet received my Devantech CMP03 compass module

Be patient, I will be

Flid

[Flid]

I put connectors where the accelerometer was and connected a remote board with accelerometer and I2C camera from wiimote. This works fine.

Amazing, I'm looking on internet about Wiimote IR camera, on Google, and i'm impresive by the possibility of this cheaper caméra.

Many libraries about this camera with this hack under .net

this add-on will be implemented on my robot.


Amazing , I'm looking on internet about Wiimote IR camera, on Google, and i'm impresive by the possibility of this not cheaper caméra.

Many libraries about this camera with this hack under .net

this add-on will be implemented on my robot.

Other, but interresting too
I will put too one 2.4Ghz vidéo camera, with OpenCV (in fact Emgu libraries in .NET ) for vision of the true world.

So I'm very impatient to see the release of DCMP and RobobuilderLib from l3v3rz

See You

[Flid]

Have you interfaced any I2C sensors yet ? if so which ones and how about some pictures to show what you're up to.
l3v3rz

In fact, not yet

Not yet received my Devantech CMP03 compass module

Be patient, I will be

Flid

Devantech CMP03 compass module received

Try under .net with my PC and USB-I2C and working well ( done one little software to read I2C components )

I know the .net dev platform but not really ATMEGA128 and AVR compilation with C ( question will coming later )

So l3v3rz, I need your wrapper with DCMP and RobobuilderLib

Take your time , I go in holidays for 1 week
I hope you will make the release when I be back

See You

[Flid]

Hi l3v3rz,

I rebuild DCMP and RobobuilderLib to test the I2C and working well with ACC Sensors This afternoon, I will make the hard modifications on Humo to include the compass. So, see you later

Here rebuild: DCMP_RobobuilderLib_with_I2C_beta_from_Flid.zip

Thank you again at l3v3rz for your work

[l3v3rz]

Ok great - official release out real soon now

Its also built into the BASIC as well so for doing rapid prototypes could be a good alternative. when you get your compass code working hope you can post and I'll add to the library

cheers