I'll add pictures soon. I have the DD apart enough to get the circuit board out. For some reason the circuit board did not want to budge. I thought maybe Irobot
added a retention point other than the two at the top. After a lot of struggles it finally came out.
My Create uses the three cargo port digital output pins for camera control.
DOUT0 = Power on camera and Propeller.
DOUT1 = Move camera up
DOUT2 = Move camera down
On the dirt dog I'm going to use:
main-brush motor on - camera on
side- brush motor on - camera down
vacuum motor on - camera up
The first one is easy to find since Irobot
included the mounting points for a through-hole MOSFET for the main brush motor. The other two may take some digging. Gordon's schematics will hopefully have the info.
I'll also need BAUD rate change, ground and VCC connections. VCC is used to power the BAM, which is one reason it is cheaper than a rootooth. It has no power regulator.
The other design decision I'm making is to use a BAM instead of a rootooth. I will have to wire it in but at $40 cheaper than a rootooth its worth the effort.
The dirt dog controller board appears to be a swivel wheel board minus the jacks and components for the vacuum motor and dirt detector. I wonder if all swivel wheel 400 series only have a single dirt detector. The missing socket is half as wide as my old disco's
The PCB power regulator and servo show in the create based pictures will end up inside the dirt bin. I will need to make an opening for the servo arm and camera power lead.