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Topic: Arduino as ISP - Using two arduinos (Read 1 time) previous topic - next topic

juanps90

Hello, I have a question regarding the installation of a bootloader using two arduinos.

1. Does the arduino used as programmer need to have a preinstalled bootloader?
2. "On the Arduino Uno, you'll need to connect a 10 uF capacitor between reset and ground (after uploading the ArduinoISP sketch).": Do I need to connect a capacitor to EACH arduino ( ie two capacitors ) ?
3. I see other howtos show different connection diagrams involving ICSP connectors. Are they necesssary?

Thank you very much !

foliveira76

No, you only need one on the one you want to write the bootloader. Just did it myself couple of min ago.

Cheers

retrolefty


Hello, I have a question regarding the installation of a bootloader using two arduinos.

1. Does the arduino used as programmer need to have a preinstalled bootloader?
  Yes, as there has to be a way to upload the arduinoISP sketch into the board so it will become a programmer board.
2. "On the Arduino Uno, you'll need to connect a 10 uF capacitor between reset and ground (after uploading the ArduinoISP sketch).": Do I need to connect a capacitor to EACH arduino ( ie two capacitors ) ?
No, just the board that is loaded with the arduinoISP sketch.
3. I see other howtos show different connection diagrams involving ICSP connectors. Are they necesssary?
They should all be doing the same function of wiring the ICSP signals from the programmer board to the target board. Show a link if one is confusing you.
Lefty


Thank you very much !

foliveira76


....
2. "On the Arduino Uno, you'll need to connect a 10 uF capacitor between reset and ground (after uploading the ArduinoISP sketch).": Do I need to connect a capacitor to EACH arduino ( ie two capacitors ) ?
No, just the board that is loaded with the arduinoISP sketch.
...



Strange, The only time i was successful was when i put the capacitor of the arduino programmer (the one that has sketch). Probably lucky..

retrolefty



....
2. "On the Arduino Uno, you'll need to connect a 10 uF capacitor between reset and ground (after uploading the ArduinoISP sketch).": Do I need to connect a capacitor to EACH arduino ( ie two capacitors ) ?
No, just the board that is loaded with the arduinoISP sketch.
...



Strange, The only time i was successful was when i put the capacitor of the arduino programmer (the one that has sketch). Probably lucky..

I think we are saying the same thing. Again, An arduino board that is first loaded with the arduinoISP sketch then needs it's auto-reset function defeated (with a cap). The target board (that which will have a new boadloader burned onto it) does not require the cap.

Lefty

juanps90

Thank you for your replies.

So thats it? No more connections required? Just plug n' go?

focalist

#6
Nov 23, 2012, 10:55 pm Last Edit: Nov 23, 2012, 11:04 pm by focalist Reason: 1
Well the data lines and ground of course.  It's remarkably simple, I picked up some ATMEGA8 chips for around a dollar fifty each.. They are the same chip as an Arduino (some very minor differences) except for the 8k vs 32kflash size.  Using a bootloader/config designed to run from the internal oscillator, you can then eliminate the crystal.  I've done this for very simple projects, things like PWM mixing of RGB LED strips.  Super minimalist, I recommend trying it (with and without bootloader) just as a learning experience...

I ended up getting one of the USBASP things off of ebay for a couple of dollars.. But in reality, if you look closely, it's actually an ATMEGA chip presumably running code extremely similar to the arduino-as-ISP code.. Which I think I am going to see if I can build a dedicated atmega isp burner, just for the sake of doing it.  Atmega8 are now $1.19 on ebay in single quantity.. The perfboard and ZIF socket is going to cost more than the chip....

I think we are goung to see a lot more of this as the prices on ATMEGA chips continues to fall.. I have seen raw 328's just over two dollars and bootloaded for two fifty to three dollars already...
When the testing is complete there will be... cake.

juanps90

I am following this guide:

http://arduino.cc/en/Tutorial/ArduinoISP

I guess all the connections you mention are included here?


simplex

If you want to program a stand alone target AVR you need a single Arduino UNO.
Just follow this tutorial:
http://pdp11.byethost12.com/AVR/ArduinoAsProgrammer.htm


Osgeld



Hello, I have a question regarding the installation of a bootloader using two arduinos.

1. Does the arduino used as programmer need to have a preinstalled bootloader?
  Yes, as there has to be a way to upload the arduinoISP sketch into the board so it will become a programmer board.




for the reasons of this questions I agree, but I want to go circular, as I have a non bootloaded 168 that I loaded the ISP sketch onto using an ISP programmer, that I now use as a stand alone programmer ... point still stands you need a way to get the ISP sketch on the chip before you can use it, easiest is to use a bootloaded chip
http://arduino.cc/forum/index.php?action=unread;boards=2,3,4,5,67,6,7,8,9,10,11,66,12,13,15,14,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,86,87,89,1;ALL

retrolefty




Hello, I have a question regarding the installation of a bootloader using two arduinos.

1. Does the arduino used as programmer need to have a preinstalled bootloader?
  Yes, as there has to be a way to upload the arduinoISP sketch into the board so it will become a programmer board.




for the reasons of this questions I agree, but I want to go circular, as I have a non bootloaded 168 that I loaded the ISP sketch onto using an ISP programmer, that I now use as a stand alone programmer ... point still stands you need a way to get the ISP sketch on the chip before you can use it, easiest is to use a bootloaded chip


Circular indeed. You kind sir are a knight of the nerds, of the first order.  :D

Lefty

juanps90


If you want to program a stand alone target AVR you need a single Arduino UNO.
Just follow this tutorial:
http://pdp11.byethost12.com/AVR/ArduinoAsProgrammer.htm




That is so much better!! I have not tried burning the bootloader because I still have not received my second arduino but I think I am going to give this a try!

Thanks !

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