Key matrix design question
Jimmy W.
Posts: 112
After playing with and sort of getting my AMX capacitive sensor working, I figured I would tackle something I was asked to do long ago, making a better PS3 home automation interface, I plan on using the guts from the PS3 bluetooth remote control, I figured out 1-9 are my rows with random buttons being assigned to the columns for pins 9-28, that leaves me with the following design that I just threw together, pins 1-8 are the source and they supply to the other pins inputs.
Does anyone see how this can be improved / pin count lessened? I am planning right now to use 4 i2c 8 bit io expanders, in the end I will have network, serial & IR as control sources with full discrete power on/off.
Oh, the extra transistor is to trigger start seperate, the only time 2 buttons need to be pressed is when you assign the remote, so I can press start and enter at the same time.
Sorry for the size, Visio isn't really my forte, but it works for a quick and dirty drawup.
Jimmy
Does anyone see how this can be improved / pin count lessened? I am planning right now to use 4 i2c 8 bit io expanders, in the end I will have network, serial & IR as control sources with full discrete power on/off.
Oh, the extra transistor is to trigger start seperate, the only time 2 buttons need to be pressed is when you assign the remote, so I can press start and enter at the same time.
Sorry for the size, Visio isn't really my forte, but it works for a quick and dirty drawup.
Jimmy
1245 x 821 - 84K
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