All i-Motors have 7 ports of I/O that each can be a digital input, digital output, certain functions like encoder input (refer to i-Series Manual for specifics) and Analog input.
All I/O are 5 VDC, TTL, and CMOS Driven. If 24 VDC I/O is needed, it must be sinking.
Each I/O port can take 15 mA sinking or supply 4 mA sourcing. This means that careful thought of current-limiting resistors must be used when installing I/O.
There is a cable that converts the 5 VDC I/O of the i-Motor to 24 VDC I/O. Refer to the i-Series Manual (Appendix F) for specifics on this cable.