FLOATING MIDIO128 OUTPUTS FOR ALTERNATE CONTROL INPUTS

[Billmac]

If you want access and ability to drive the outputs from another source, you can carefully cut circuit connections to the Output Enable pins of the chips and connect them together to a logic input that lets you float the outputs and take control from another bus.  This is what I did in my piano/organ to drive outputs either from MIDI data or from another set of bus drivers with keyboard contact inputs.  Of course the other bus must be floated when the MIDIO128's are enabled so that bus contention cannot occur.

[ilmenator]

Interesting... what's the schematic you're using?