ZERO DELAY USB JOYSTICK - AUTO ANALOGUE MODIFICATION

This is an additional project to the Zero Delay USB Encoder True Analog Joystick Modification.

You need to have successfully modified, tested and calibrated the Encoder in the previous project before adding this device.

When completed and working it takes away the annoying feature of the modules habit of always starting up in Digital mode - which means you need to select Analog using the mode switch every time you want to use it.

UPDATE: (feb 2021) Before you get stuck in to making this - I updated the main project in Feb 2021 to say theres an easier modification than this little gizmo... but if you really want to make it heres the info..... Enjoy

What this project does is to mimic you pressing the mode button ONCE to get it to Analog mode - using a time delay (resistors and capacitor) to operate a transistor as a momentary switch.

The sequence only starts once USB connectivity is established with the computer - by taking the +5v supply (approx) which feeds the RED Led (Digital On) and using that to start the timing which is just the charging of C1.

Once the transistor is switched on the Encoder see's that as a single MODE switch action and it switches to Analog.

Once in Analog mode the RED Led goes off - turning off the Timer circuit and the GREEN Led turns on and the Encoder works in Analog mode ! (Simples!).

Its important to note that if USB connectivity with the PC isn't established - it won't start the Encoder or the timer!

So just testing the Encoder on a 5V USB supply (no PC) isn't going to work !

I added a reset button just to prove I could manually restart it without having to unplug the USB every time.

If you can solder in a tidy fashion and have worked with stripboard or Vero board before its easy to make. (And if you haven't - its still not difficult!).

Once constructed you need to make 3 connections to the Encoder as described in the text.

I have included photos which show how I made mine (as small as I could) with what I had available at the time.

Vero board / stripboard - 12 holes long x 4 or 5 copper strips wide - see photos - only 1 track needs to be cut on this.

Transistor:

1 x BC107 or BC147 or BC547 or almost any general purpose silicon NPN type. Correct B-C-E orientation is essential.

Resistors (3):

1 x 39k 1/8 or 1/4 W

1 x 470k 1/8 or 1/4 W

1 x 220 ohm 1/8 or 1/4 W

Electrolytic Capacitor 1 x 1000 uF - 6.3 to 25 volt

Wires to suit.

Optional: (see wiring diagrams)

1 x push to make switch (reset)

1 x on/off switch SPST

Collect together all your parts before you begin.

Cut your Vero board to a size suitable for the components you are going to use.

I recommend a trial fit of the components before committing to cutting your board and the track to size in case yours doesn't work out quite like mine did.

Use my photos for reference to achieve the end result.

Double check connections with the schematic diagram.

If space is not a problem in your project construction its up to you how big you make it - only the correct connections are important here.

My board was 12 holes long and 5 strips wide - but as you can see I could have got away with 4 strips.

The layout you choose might mean you don't need to cut any tracks at all.

The photo shows all components fitted and an extra switch (optional) which I added to force selection of Digital (yes - Digital) mode to use as a reset to prove correct operation.

Without that I would need to unplug the USB from the PC to test it each time. With the switch added I could just press it, watch the GREEN Led go Off, and the RED Led turn On (starting the Timer) then a few seconds later they would swap back to GREEN On and RED Off.

If you wanted to go a step further because you have a need to switch to Digital sometimes and stay there, you can add an On/Off switch (S1) into Line A and when On the Auto Analog Timer works as it should and when Off will allow you to operate the Mode switching manually using the extra switch S2 (not shown).

The diagram shows in the Green box the new circuitry (on your new board) and in Yellow the Encoder module connections that are relevant here. You don't have to understand it - just wire it all up correctly - and remember - no further tracks to cut on the Encoder.

On the Encoder:

A = Junction of the +5 volt feed from the Encoder chip (Black blob) to R10 which feeds the RED Led. The end of R10 nearest the Blob is the one to use.

Note the wiring supplied by the Chinese makers which plugs into the Encoder Mode socket appears to use RED for ground (0v) and Black for switching - so don't assume colours are logical - Check for yourself !

B = Mode switch input connection.

C = 0 Volts - (and second Mode switch connection)

A = Timer start feed from Encoder

B = Black wire to Mode switch connection - see photo next section.

C = 0 Volts - (and second Mode switch connection)

As you can see from the photos - just 3 connections - no tracks to cut or alter on the Encoder - its as easy as A-B-C !

A = One wire to solder to the back of R10 - take care not to short anything out.

B = Black wire to Mode switch connection - see photo next section.

C = 0 Volts - (and second Mode switch connection)

DOUBLE CHECK YOUR WIRING BEFORE CONNECTING UP USB TO THE PC !

Now you should find when you connect up to the PC USB socket, shortly after the RED Led turns On, it will go Off and the GREEN will turn on - and thats the Encoder now in Analog mode without you having to do it yourself.

Note the R1, R2 and C1 component values I used gave a suitable delay to get it to work reliably. Depending on the age and quality of the components you use the delay could be slightly longer or shorter. A large value for C1 (say 1500 uF) should theoretically take longer for the switch-over to occur.

Have Fun !