74LC151 is an 8to1 input multiplexer.

i used 2x 74LC151 for the whole sequencer, clocked by the same signal and they also share the adress-pins on the controller, so they run completely in sync.

each one has one dataline that gets fed back into the controller.

total pins for the inputs so far : 6

photo copy

i will add another MUX for the rest of the buttons, like “play” “up” “down” etc.

that would use another dataline so all in all 7 I/O ports on the controller, of 13 possible I/O ports

i need five non-MUXed outs for triggering the sounds.

and if i manage to use the same clock and adresslines as in the input MUX’s i can use one single line for muxing 16 LEDs.

so either i will use the analog inputs which the controller has 7 (!) as inputs from the input MUX’s or buy the next bigger processor, which is a 54 I/O beast 🙂

thats whats going on at the I/O ports of the controller

untjlasaitled Kopie


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s