7I92 15
OPERATION
INTERFACE CABLES
Mesa daughtercards use a male to male DB25 cable to interface to the 7I92. For
noise immunity and signal fidelity it is suggested that only IEEE-1284 rated cables be
used. IEEE-1284 rated cables have a twisted pair shield wire for each signal wire and an
overall shield terminated in the metal connector shell. This results in much better
performance than flat or NON-IEEE-1284 parallel port cables For short connections of less
than 3 feet, flat cables can be used. No other type of cable should be used.
Mesa can supply IEEE-1284 cables tested with the 7I92 / daughtercard combination
in 3, 6, and 10 foot lengths.
BREAKOUT POWER OPTION
When used with Mesa breakout/daughter cards, the 7I92 can supply up to 1A of 5V
power to each of the daughter cards. This option is disabled by default to avoid possible
damage to standard breakout boards, so must be specifically enabled for Mesa
daughtercards. If you use this option you must verify that the interface cable does not tie
the eight parallel port ground wires together as some cheap printer cables do. Mesa
supplied IEEE-1284 cables are the best option for Mesa daughter cards and are
guaranteed to work with the power option. Flat cables will work as well but have poorer
noise immunity and signal fidelity.
PLUG AND GO KITS
Motion control kits with pre-programmed 7I92, interface cable, and daughtercard(s)
are available to simplify system integration.