Wired remote for Pioneer HU

[mister_e]

one thing I would make sure before connecting this to the car... measure the .spurious/floating) voltage on the tip pin when nothing it pluged.. if it's 12 volt you want to change some part of your hardware. Case it's 5 volts (or so), well there's no problem with your current solution

What you need to do is to clear the PORTB bits (to 0) and set your TRISB bits to 0 when you want to set a resistor to ground, and to 1 when you want to disconnect the resistor from the circuit. The more you clear TRSIB bits, the more resistor you add in parrallel. You should know how to calculate/evaluate resistors in parrallel, so, just etablish some value and work around this. Maybe you don't need more than 3-4 resistor to reproduce the whole value in the table above. If you feel lazy, then use 8 resistor and assign them to a whole 8 bits port. easier, need a bit more I/O... but easier. BTW you already get the idea as per your code.

8 resistors, 6 button = 14 I/O, a PIC 16F628 will do the trick without any need for a matrix keypad.

Button1 VAR PORTA.0
Button2 VAR PORTA.1

IF Button1=0 then set your resistor on portb
If Button2=0 then set your resistor on portb
.....

or

Button var PORTA
Select Case Button
     Case xyz
          Set yourresistor
     Case abc
           Set another resistor
....

How about that?

[fratello]

Thank You verry much for support !
I use matrix keypad because the Renault remote act like one (see picture) !

What you need to do is to clear the PORTB bits (to 0) and set your TRISB bits to 0 when you want to set a resistor to ground, and to 1 when you want to disconnect the resistor from the circuit.

So, it's enough (?) something like this :

case 1
portb.2=0
trisb.2=0
pause 500 ; i put the resistor on portb.2 to ground for 0.5 sec
portb.2=1
trisb.2=1

The "portb" it's OK to set in header "PORTB=%11111100" ?

[pedja089]

Set all pin to low, and then just change tris registers, instead of changing port and tris.
Also add 5.1V zener between resistor common wire and ground.

[fratello]

Now it's ok ?

   '// Define port pins as inputs and outputs ...
   TRISA  = %00000111
   TRISB  = %00000000


include "c:\pbp\keypad2.pbp" ' see http://www.picbasic.co.uk/forum/showthread.php?t=3250

main:
gosub keypadscan
gosub check
goto main

check:
select case key 
case 1     ; volume down
portb.2=0
pause 500 ; i put the resistor on portb.2 to ground for 0.5 sec
portb.2=1

[mister_e]

PORTB=0
TRISB = 255 ' Disconnect all resistors from the circuit
' Some code here
DoItAgain:
          SELECT CASE XYZ
                    CASE ABC
                              TRISB.0 = 0 ' Connect PORTB.0 resistor to the circuit
                    CASE DEF
                              TRISB.0 = 0 ' Connect PORTB.0 resistor to the circuit
                              TRISB.1 = 0 ' Connect PORTB.1 resistor to the circuit
                    CASE GHI
                              TRISB.0 = 0 ' Connect PORTB.0 resistor to the circuit
                              TRISB.2 = 0 ' Connect PORTB.2 resistor to the circuit
                              TRISB.3 = 0 ' Connect PORTB.3 resistor to the circuit
                    END SELECT
                    PAUSE 500
                    TRISB = 255 ' Disconnect all resistors 
                    GOTO DoItAgain

[fratello]

THANK YOU ALL !

@ DEVICE pic16F628A, INTRC_OSC, WDT_OFF, PWRT_OFF, BOD_OFF, MCLR_ON, LVP_OFF, CPD_OFF, PROTECT_OFF 

   
   Include "modedefs.bas"   ' Serial Protocol
   Define   OSC 4           ' 4MHz 
   CMCON = 7                ' Disable on-chip comparator, PORTA in digital mode
              
   '// Define port pins as inputs and outputs ...
TRISA  = %00000111
PORTB=0
TRISB = 255 ' Disconnect all resistors from the circuit


include "c:\pbp\keypad2.pbp" ' see http://www.picbasic.co.uk/forum/showthread.php?t=3250

main:
gosub keypadscan
gosub check
goto main


check:
select case key 
case 1     ; volume down
    trisb.2=0

case 2    ; track -
    trisb.3=0
   
case 3    ; volume up
    trisb.4=0
   
case 4    ; mute
    trisb.5=0
   
case 5    ; source
    trisb.6=0
   
case 6    ; track +
    trisb.7=0
   
end select
Pause 500 ' do it for 0.5 sec
TRISB = 255
Return

end 'of story !

[mister_e]

Time to celebrate!




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