ARC Release 2013.01.12.00

Download and install the latest ARC robot programming software to experience these updates.

Download ARC
Software Information
This release is minor and the update focus is on the EZ-Script i2c read/write commands. The i2c is normally a confusing protocol due to the addressing issues. I have created the i2c commands in EZ-Script to figure out all addressing conversion for you:)

Click here to read about i2c:

Click here to locate the i2c port on your EZ-B:

For example, the confusion behind the i2c addressing lies in shifting the 7 bit address into an 8 bit address, and setting the LSB to 0 or 1 depending on the direction of the data. Does that sound confusing? Good, because you do not need to worry about any of that with EZ-Builder!

If you communicating with an i2c device (for example an Arduino or Compass, etc) - you may be given one of many address types....


Device Address: 0xa0


Device Address: 0x50


Device Read Address: 0x50
Device Write Address: 0x51

The above list of addresses are all the same - surprisingly. In any other environment, you would need to understand how they are the same to know how to use them. You would need to convert between 7 bit and 8 bit of 0xa0 to 0x50. You would then also need to convert the 0x50 to 0x51. Wow, so confusing! Well, EZ-Builder makes it easy.

In fact, you can use ANY i2c device address - without needing to format or convert the bytes. EZ-Builder will figure it out for you:) You simply connect the device to your i2c port, read the manual to find the i2c address, and enter it in EZ-Builder's EZ-Script i2cWrite() or i2cRead() commands.

- Release() fix
- i2cWrite() and i2cRead() do not need device address conversion
- Change tracking color by ControlCommand(). See below example

Tracking Color Change Command


ControlCommand("Camera", CameraColorTracking, "Red" )
ControlCommand("Camera", CameraColorTrackingEnable, "Blue" )
Accuracy of a pot is about 2-3 bits unless you go to a higher price of a multiturn then looking at 5 bits
accuracy of magentic encoder is 10 bits and can get them up to 14 bits

Voltage output on both are the same ,both put out 0-5 volts level and both are connected to the wheel
so better replacement to pot is magnetic encoder,since they really do the same
not really counting the ticks on a magnetic encoder

here is some info off the site usdigital that mostly makes encoders

Analog output provides an analog voltage that is proportional to the absolute shaft position. Analog output is only available in 10-bit resolution.

and some info on tracking ,there are 2 types of encoders one is absolute and other is incremental

Position Control
When controlling robotic end effector's position, absolute encoders are the preferred solution. US Digital absolute encoders are unique in the market as they offer high performance without the complicated communication protocols normally associated with absolute encoders. The compact size of the miniature magnetic MA3 encoder means that absolute encoders can be used in creative and tight spaces; the designer no longer needs specialized hardware or software to interact with the encoder, opening up a new world of possibilities.
So my question would be; How would this MA3 encoder interface with the EZB? Through the ADC port? Would it return the voltage values just like a common pot?

DJ, I didn't know you had the coding section up and ready. Wow, that was fast! I'll get my codes in there asap.
Wow, that little sucker costs over $70! Sure looks nice though and sounds likes it returns voltage readings like a regular pot. very tiny also.
They make others under $30 small size,but on that one i bought 6,if you buy 5 or more price drops alot
dont forget when you deal with higher precision and smaller size price is high

Also another point most pots DONT DO 360 deg ,witch is what is needed on a motor feedback

I did find some but at a cost of $50 and there are big
ADC takes 0-5 volts ,and both put out 0-5 volts ,its not like digital,so interfacing is the same

I SELL high torque motors from neato xv-11 and they come with magnetic encoders,they put out the same voltage
robotmaker, I think this part could help me. I need shaft position feedback, but let's say I have 60 turns of the shaft. I don't want to mess with gearing to get the shaft turns to something reasonable for a feedback pot. This peice is not limited mechanically, right? It will continue to rotate mechanically and just reset it's analog output?
i think so, never tested it

ALSO for others, regular pots are not 360 deg continuous and even multiturn they have a metal stop inside,they work great for servo position ONLY.

So only magnetic hall effects encoders can be used on motors for navigation and speed with analog output ,second can only tell if going foward,unless you have a differential circuit.

On quaderature optical encoders have 2 outputs 90 deg to each other and has ciruit to tell in going foward pulse or backward pulse ,by comparing the pulses.

When i get a chance and time looking at making pulse width to analog voltage out circuit.