C64 mini Quick doodle for the USB hub mod

Had someone ask, so here’s a quick and rough explanation

You need to make SIX solder connections

First, lift the centre two pins of USB1 on the mini

Second, cut off the plug and solder four pins from the USB hub cable to the bottom of the USB1 connector pads on the PCB

Third, cut off the mini USB of the longer USB cable and create a bare end. Solder two data wires to the lifted pins on the mini’s USB connecote

This then attaches the USB hub in full to the minis processor

And just uses the physical connector on the mini as an extension of one of the sockets on the hub!

C64 Mini Keyboard, 1/2 alive and Some CAD

Bit of a change of pace from the electronics, onto the CAD…Here’s a first draft of the first key on the C64 Keyboard – the Left Arrow!

Done at full scale, then at 50% scale

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C64 Mini Keyboard – Some progress!

Not much really – Shift Lock keys just arrived off the slow boat. The pinouts are confirmed, I’m going to hit ‘go’ to manufacture after another quick check on the PCB

Also, from a bit of researching, i’m not so sure the Diodes are needed.

I may have to make two batches of board, one with, one without

 

C64Mini Keyboard – PCB Layout Success

C64Mini - Final PCB Revision Maybe

After a loooong weekend and sneaking in a few hours – Success with the keyboard layout dimensions!

There’s few tweaks here and there remaining to align things perfectly and also to add some nice Silk Screen artwork

And, how I got there!

Continue reading “C64Mini Keyboard – PCB Layout Success”

C64 Mini Keyboard mod – More Electronics Part II – OOPS

After spending a while lining up the buttons and generally making the PCB layout a bit tidy, I figured I’d print a 1:1 and see just how well it aligns….

 

Oops…

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Continue reading “C64 Mini Keyboard mod – More Electronics Part II – OOPS”

C64 Mini Keyboard Mod – The Electronics

As mentioned before, there’s loads of ‘keyboard matrix’ tutorials out there, so, i’m going to not bother with any of those yet and work backwards a bit.

IF i’m making a micro C64 Keyboard for a mini C64, I mayaswell make the thing backwards compatible so that it could be used on a real C64…

The C64 Matrix…………(image pinched from THIS PAGE) 

C64_Keyboard_Schematics_PNG

 

This it’s quite quick to knock this up in EasyEDA

The Shift Lock key looks  a bit ‘odd’ as it just parallels up with the shift key.

I’ve thrown in some Debounce diodes also – because all the top mechanical keyboards have it, so why can’t I (no idea if this is a good idea yet, but easily removed before I get a PCB finalised) I’m not too worried about the Arduino bits yet – i’ll bolt on the decoding circuitry later – this is still just an excercise to see if it’s possible!

C64 PCB Matrix

This isn’t the first version – The pic shows the newest footprint before I figured out the issue below

After creating my own custom SMT switch footprint / component and arranging the parts on the board – I hit a few snags – Have a look at the layout below…. you’ll see that the SMT legs just stick too far out

Easy enough, rotate every other switch so some are ‘up / down’ , some are ‘left / right’ with the pads.

That does fit – just, BUT, i’m going to have to cut a leg off 5 or more switches to stop them mechanically fouling and electrically shorting!……D’oh!, Possibly back to the drawing board with the switch choice?

C64 PCB Matrix - SMT BAD VERSION

The diodes i’ve chosen (for now) are a larger SOD123 package, about 2.6 x 1.5mm or so…one of the larger packages and I just happen to have a few in the shed (somewhere!)

The row of connectors on the right is just a generic 2.54mm space 20 way header. This’ll probably not be populated in my ‘final’ version that sits inside the Mini, BUT, i’ll leave the pads on the PCB so it could be turned into a genuine working C64 Keyboard 🙂

Wanhao Duplicator 9 – New X Axis parts coming

It’s been a busy personal and work life for the past few weeks so it’s been difficult to ‘tinker’……….I have however made something new!………….. Continue reading “Wanhao Duplicator 9 – New X Axis parts coming”