If anyone's interested, here is the finished code for Leinad Legobot. The new 4000 routine detects touch sensors to make the forklift stop at its upper/lower limits, rather than keep moving even though there's no place to go. We couldn't get it working with the optical sensors (various reasons) so I called an audible to switch to the touch sensors. That works much better. Kudos to Dan for perfecting the code behind this. Kudos also to Paul H. for teaching me (several versions ago) what was wrong with my joystick navigation code. Plain text version: http://www.vcfed.org/evan/lego/robot.txt Easy-on-the-eyes version: http://www.vcfed.org/evan/lego/robot.pdf My plan now is bring this to Trenton, exhibit it at Southeast, expand it into a game at Kfest (if I can go), and then make it the centerpiece of the permanent Lego learning station in our museum. I'll make a big kid-friendly flow chart poster to go with that last part. ________________________________ Evan Koblentz, director Vintage Computer Federation a 501(c)3 educational non-profit evan@vcfed.org (646) 546-9999 www.vcfed.org facebook.com/vcfederation twitter.com/vcfederation