Uberben, the location between the N and arrow key, or to next to the right Control key seems fine to me. Will a teensy be able to present either of these joysticks as a USB joystick HID device?
Yes, a teensy should be able to report the joystick as an HID joystick, HID mouse, HID keyboard, HID MIDI controller, just about anything. My plan is to design my own controller board and use the
LUFA USB stack, but I will be using the same chip as the teensy, and my prototyping board is
this one from Adafruit. I chose it over the Teensy primarily because it is open source (hardware and software), unlike the teensy. I believe the ATmega32u4 chip on those boards can report around 6 simultaneous USB endpoints, so I can use the one controller to do the keyboard, mouse, and even add a gaming mode where the joysticks are actual gamepad joysticks.
I used an Apple 360 scrollball scavenged from an Apple Mighty Mouse in the notch of the left thumb cluster. It is used for page scrolling. The trackpoint is in the right key well for cursor movement. I wanted to have the trackpoint do both functions by holding down a key for scrolling pages. Can that be possible with these you found, Überben?
I saw your scroll ball mod, which was part of my inspiration for this. The mighty mouse scrollball seems similar to the ball on many older BlackBerries/Android phones. I like the 4-directional scrolling it provides, but I've not been overly fond of the fact it feels like it has notches when it rolls. Scrolling with a TrackPoint is
very nice. Variable speed, no need to lift a finger for long scrolls, etc. I plan to implement something like this with my build, either with a toggle on the one joystick or by using a second joystick just for scrolling. There should be no problem getting my joysticks to do this other than having to put time into coding it. My only fear is that the mouse HID standard doesn't implement the smooth scrolling that the TrackPoint driver does. Worst case scenario, I will have choppy scrolling until I implement a custom driver.
Hopefully I can get a proof of concept up soon, but I will probably have to wait to get some PCBs made and it is looking as though my job might hit a busy period soon. I'll try to post a video once I get something going, though.