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PowerSwitch questions: ISP Connector and ATtiny2313

Posted: Sat Jul 14, 2007 11:38 pm
by Aurora
I am glad to have found your Project, since I want to use it to enable a Linux Server to switch on and off Periphericals and maybe later more. For example it should switch off the Laserprinter if there has been no job for a couple of minutes and turn it back on if a new job comes in.

Wenn now to the question. It has been a while since I did Electronics, so thiese questions may be a bit dumb.

First question is: What is the meaning of the "ISP Connector" - What does it connect to? I see there is a USB Connector (in the left) and Power from the Transformer (top right). So what is this ISP Connector there for?

The second Question is: If I use the ATtiny2313, can I use the circuit schematics provided without change or are there changes in the pins/voltage or anything else? Do I have to make changes in the firmware or program code? My knowledgle of C-Programming is little more thatn "./configure && make", so I hope this will work on my Gentoo system.

Many Thanks
Aurora, Germany

Posted: Sun Jul 15, 2007 6:41 am
by iphi
ISP means In Circuit Programming
It is used to burn the program code into the AVR.
Google for PonyProg for an explanation and circuit.

The ATTINY2313 will work fine without changes to hard- or software.
But: You need to burn the fuses correctly to enable the external crystal oscillator with prescaler 1. By default this device runs on the internal RC oscillator.

Posted: Mon Jul 16, 2007 3:50 pm
by christian
Thanks, iphi, for answering these questions. I should mention that we already have a Makefile target for programming the fuses. Type

make fuse_tiny2313

to set the fuse bits to the correct values.