Friends:
Regarding the Sparkfun Protoshield. Can someone explain the ICSP connection from the Arduino to the shield? I notice only three pins connect to the shield. (Out of 6 that normally connect to the Arduino) What is the reason behind this? Does the shield have to be removed for the Arduino to be programmed?
Thanks all,
Migs
You didn’t give us a link, so not sure which one you are talking about, so not sure exactly, but…
The older version of arduino didn’t have the “reset” pin brought out to one of the header rows. Now it is brought out to the header row next to the +3V3 pin.
The only place this pin was brought out was one of the male pins on the 2x3 ICSP header
This meant that when you had a shield that covered the physical reset button, you couldn’t reset the arduino easily.
To overcome this, some shields had a downward pointing female header that picked up on the reset pin on the ICSP header. This could then be connected to a button on the top of the shield, so that the arduino could be reset with the shield in place.
In the included picture notice how the SparFun Protoshield has only one female header with three pins to mate with the Arduino’s six pin ICSP header.
http://farm3.static.flickr.com/2495/416 … 7299_o.jpgAll signals used on the ICSP header except reset are also available on the regular headers.
