So much for the TI-89

Apparently, the data I/O output signal has been changed in the TI-89. Frequently, an extra "pulse" is detected by the camera. This utterly screws up the whole mirror lock up routine. Without putting a scope on it, I suspect the TTL level changes are not as long as in the older TI-83 model. Guess I'll keep the TI-83 and give up the shiny new TI-89.