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Fez Mini and the boe bot


#1

I bought the fez mini to convert over from the basic stamp 2 on my boe bot. I bought the Sd card attachment also. I will catalog the conversion of existing things I did with the boe bot here. First with converting it over to my maze solver robot and then to my line maze solver.

The first issue i ran into is 2 large caps behind the basic stamp mounting point did not allow clearance enough to mount the mini with the sd card part attached. I desoldered one of the caps to tilt it back and it allow it to be plugged in enough to be stable and fit.

As i do more of this i will post code to interface with the various devices i am pluging it into on the boe bot.


#2

Thanks for the info. This and more details should help other users coming from stamp


#3

The PWM pins don’t match up to the BOE/BS2 so you will have to move the second continuous servo to port 15 on the BOE. So you have 2, one in port 12 and one in port 15 which map to Di6 and Di9 on the FEZ mini. If you run a extra servo for like the sonic sensor you must find a different port then the obvious place where power and pwn would normally be provided.


#4

You can use output compare to generate PWM on any pin. But, using PWM is done in hardware so using PWM is preferred over using output compare.


#5

Yes i am moving those pins(13,14) on the BOE over to output compare. I was making sure it was known they could not do PWM directly like the nice example in the book.


#6

So everyone know where this is at. I am letting a friend borrow it to use for while so i will not be providing updates for a while. I am to busy with my new robot and the fez domino to spend my time on it at the moment. I believe my friend will be posting a new IR class from his work on the boebot that everyone will get use out of so at least its being loaned for a good purpose.


#7

Hi all,

Just curious about the Fez Mini and the Boe-Bot. Is it as easy and dropping the Fez in there? Any thing I should take into consideration before purchasing?

I teach a class that uses the boe. I’d like to start using .NET if possible.

Thanks for any help,
Brian


#8

You do not need FEZ to try NETMF. You can use the emulator now to see how it goes. The videos also show more details…I LOVE FEZ and think it is the best but I work for GHI so do not take my word for it…listen to what other users will say :wink:


#9

Yes its just as easy as dropping it in there. As i mentioned some of the PWM does not match up so you need to move the continuous servos to ports that have that. Or write pwm functions for digital pins. The later should happen anyways once i get annoyed enough to do it myself or enough people complain about it and GHI does it. I do own quite a few micro controllers. I pretty much use FEZ now. If i do pull out a arduino or a basic stamp or some other chip its to use it as a slave to the fez mini or domino.


#10

[quote]…or enough people complain about it and GHI does it.
[/quote]

You can do PWM on any pin! It is already covered in the book. Here is the code too :wink:
http://www.tinyclr.com/downloads/Component/FEZ_Components_ServoMotor.cs

It use the OutputCompare feature we have to generate PWM in software…and this is much better than what arduino or basic stamp has because we generate it in the background so your code will still run while we are generating PWM in software.

Maybe I misunderstood your reply?


#11

Yes i understand what your saying. I am talking at a deeper level like creating a libary that emulates the basics of your PWM on digital pins not just pulse out.


#12

Can you please explain what is it that you want o generate and OC can’t handle? An example device/application too please?


#13

Yeah when i get home will explain better.

I would guess the main thing is consistency. ON this pin(Digital) to send out a pulse i use OC. On this pin(PWM) i use setPulse if i remeber right. Being inconsistent on base things like this make it harder for the new guy. Everything can be done in the code as you say. The real question are we consistent and easy to use so people coming from far simple languages like say basic stamp can make the conversion and under stand how to send out a 2ms pulse then read in 5 ms pulse response.


#14

PWM and OuputCcompare are completely different things. Yes you could send a PWM signal with OC but you can also send completely random signals. Methinks it would make no sense to have the same interface for two completely different functions. YMMV…


#15

no i don’t want the same. the simplest form would be to add a set pulse command to the digital pin. Can still use all your OC power and the other command i am thinking of maybe that was the serializer that had it.


#16

oh I see. It all can be done but you are saying it is easier to make a class that wraps OC and provide methods similar to PWM. If I understand this right, GHI doesn’t need to implement anything new but anyone (or GHI) can provide an example on how to wrap OC in a class that emulates PWM.

Correct?

If that is the case, this class can be done in 10 minutes…even better, I will make a project page for it :smiley:
(link removed)


#17

Yes exactly.


#18

page is updated with code


#19

Thanks everyone for the answers. I’ll take your advice and play with the emulator first.


#20

Just remember that the emulator doesn’t emulate the “GHI” libraries. Those are made to work on GHI devices only :slight_smile: