no stress multi-chip programming

so went down winding path of trying find /build device make life easier , succeded in doing opposite. when took step , cleared mind did find solution.

i wanted upload sketch multiple chips without pulling them in , out of arduino. not stress board , chips. after time trying wrap newbie head around advanced project, stopped , started again , hit me.

i started plugging zif breadboard , plopping atmega328 in it. pulled atmega uno , set aside. used jumpers jumpers , handy atmega328 pin map make connections each pin uno board.
i uploaded sketch arduino ide , worked! began eliminating connection 1 one until left neccisary connections. , findings...

pin 1 reset
pin 2 digital 0 (rx)
pin 3 digital 1 (tx)
pin 7 5v
pin 8 grnd
pin 20 5v
pin 21 5v
pin 22 grnd

also 16mhz crystal across pin 9 , pin 10 w/ 22pf cap. between each leg , ground.

now can upload sketch many chips want out putting unneccisary stress on arduino uno or atmega328 chips.

i hope helps avoid days of beating head against wall went through!

you don't need remove 328 arduino. load arduino isp sketch , hit ctrl-shift-u program external chips.

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