How to Multiplex 60 inputs

[nigelb]

We are often asked if it is possible to connect a large number of buttons to x10i the answer is yes, the x10i has a built in multiplexer for reading inputs over a 4ms time slice. and here is how we suggest doing it:

SuperStrict

Framework	heber.x10i
Import	brl.polledInput
Import	brl.retro


Global x10iBoard:TX10iBoard = New TX10iBoard.Create( encryptedKeyGeneric )

x10iBoard.InputMultiplexing( inputMultiplexEnabled )

Global minputs:usbMultiplexedInput = New usbMultiplexedInput 

Repeat

	x10iBoard.GetMultiplexedInputs( minputs )
	Print ""

		
	For Local bits:Int=0 To 3-1

		For Local channel:Int=0 To 4-1

			Print "Byte" + channel + " = " + Bin$( minputs.byMuxInp[channel,bits] )
		Next
		
		Print ""
	Next
	
	Delay(100)

Until KeyDown(KEY_ESCAPE)

x10iBoard.Close()
x10iBoard = Null
GCCollect

End

Rem
4ms Multiplexer                        OP12  OP13  OP14  OP15

                                         |     |     |     |
                   ___                   |     |     |     |
IP0 ----------o---o   o-->|--------------o     |     |     |
              |    ___                   |     |     |     |
              o---o   o-->|--------------)-----o     |     |
              |    ___                   |     |     |     |
              o---o   o-->|--------------)-----)-----o     |
              |    ___                   |     |     |     |
              o---o   o-->|--------------)-----)-----)-----o
                                         |     |     |     | 
                   ___                   |     |     |     |
IP1 ----------o---o   o-->|--------------o     |     |     |
              |    ___                         |     |     |
              o---o   o-->|--------------------o     |     |
              |    ___                               |     |
              o---o   o-->|--------------------------o     |
              |    ___                                     |
              o---o   o-->|--------------------------------o

 

 

) = bridge

O = connection
  ___
-o   o- = switch

-->|--  = diode 1N4148

Using this schematic you can achieve a 60 input capability using only 15 inputs and 4 outputs.
EndRem