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USBtiny with a minimalist board
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USBtiny with a minimalist board

by polarboy on Wed May 13, 2009 11:26 am

Hi, I just assembled my USBTiny and just discovered the following text

If you're not using the USBtiny to talk to a SpokePOV kit, and if you are using a target that has some load on the SCK and MOSI pins, you may need to replace R4 and R7 with jumpers as the 1.5K resistors will have trouble driving the load!

I'm going to make a minimalist target board on breadboard according to this one here
http://www.evilmadscientist.com/article ... rgetboards

so the wires are directly connected to the pins. Just for confirmation, does that mean that I don't have any load on the SCK and MOSI pins, so no resisters in between? So do I still have to replace R4 and R7?

Thanks in advance
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Re: USBtiny with a minimalist board

by adafruit on Wed May 13, 2009 12:06 pm

nope!
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Re: USBtiny with a minimalist board

by polarboy on Wed May 13, 2009 12:19 pm

ah cool, so in that case, what kind of load would you put on these pins anyways

To prevent too much current going through these pins or something?
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Re: USBtiny with a minimalist board

by adafruit on Wed May 13, 2009 1:29 pm

if you needed a lot of pins
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Re: USBtiny with a minimalist board

by John_NY on Sat Sep 05, 2009 8:08 pm

Thanks! I also picked up a USBtinyISP and some ATTINY2313 ICs, and was planning on using an EvilMadScientistLabs board to program the ATTINY ICs. I know to use the resistors now!
Thanks,
-John
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Re: USBtiny with a minimalist board

by redsleigh on Tue Oct 09, 2012 3:49 am

I too am looking to use my usbtiny with a minimalist board to program my attiny45. However, if I decide in the future to not use a minimalist board, I would have to replace R4 and R7 with jumpers correct?

Are those 2 resistors necessary when using a min board? I could just install them onto my min board, right (in the SCK and MOSI lines)? That way I don't want to mess with the usbtiny if I decide to use it with something else (other than spokepov).

Thanks for the help, still learning.
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Re: USBtiny with a minimalist board

by adafruit_support_bill on Sat Oct 13, 2012 7:51 am

if I decide in the future to not use a minimalist board, I would have to replace R4 and R7 with jumpers correct?

It is not a question of minimalist board. It is the circuit you build on it. If you have a load on the SCK and MOSI pins, you will want to use jumpers.
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