I notice in the documentation for the new official Arduino Wifi shield, it states that Digital I/O pin 7 is used for handshaking between the shield and the host Arduino, yet the schematic for the Wifi shield does not show where Digital I/O pin 7 goes to on the shield.
Can someone please clarify this connection and its usage?
Look at the picture on that page. See the green wire on the righthand picture? That appears to connect Pin 7 to something. Looks like someone screwed up the schematic and they had to add a jumper. Check the schematic to see where it goes (t pad or via just south of the 6 FTDI pins.
UPDATE: I looked at the schematic and in that area is a via connected to pin 11 of IC4 (level shifter) and nothing else. I assume the jumper from Pin 7 is going there. From the Level Shifter it comes out pin 10 and goes to a pin on the 100-pin "AT32UC3A". It's either Pin 82 (VDDIO3) or Pin 19 (PA13). Pin 19 makes more sense. You can now look at the firmware source (wherever that is) to see what PORTA bit 13 is used for.
I took the other way round and looked at the source code of the WiFi library. Seems to be some kind of slave notification that it's ready. This way the master doesn't have to always poll the slave over SPI but just waits till that pin goes LOW.
Thanks for the feedback guys! I now know where to look. I have one of these on order so hopefully I can see if they fixed this up properly or not.
UPDATE: Actually John, looking closer at the image with the jumper, it looks like the via was originally going to Dig 3 (INT1) on the Arduino header but the jumper to Dig 7 has been introduced and the original track to PD3 has been cut.
Therefore this signal after going through the level shifter is coming from (I assume its an output to the host Arduino) PA25 on the AT32 Micro.