• STM8 V-USB

    08/17/2020 at 03:10 0 comments

    I found a working version of STM8 V-USB for a HID keypad.  I have refactored and modified the stack to support Vendor Request packets.  The limitation is that (3) other GPIO pins on the same port are only available as inputs.  I got a work around for  - just turn them into PWM and you can force them individually H or L.  :)

    Here is a porototype for a STM8 version of LCD2USB that I used for debugging the V-USB stack.  LCD Smarties can be used to control it under Windows.

    It is working good enough this morning, so I went ahead and made a toner transfer PCB.

    It works first time.  :) 

    I have broken out headers for serial port, I2C as the PCB might be useful for my other projects.  I also have pads for a tiny crystal for projects e.g. LCD clock.

  • Winner Winner Chicken Dinner

    06/24/2020 at 22:01 0 comments

    Here is another simple recipe with minimum ingredients and work.

    DIY bake chicken coating:
    1 teaspoon bread crumb, 1/3 teaspoon of Chilli powder, 1/5 teaspoon salt (optional)

    I used it to coat a couple of drum sticks. 
    I made the bread crumbs from the bread ends or stale bread.  More details here.

    According to wiki, Chilli powder is chili peppers and blended with other spices including cuminoniongarlic powder, and sometimes salt.

    Salad dressing mix (dry) are good alternative spice mix to try.

    DIY Fries:

    I washed a few potatoes, and use a kitchen gadget to cut them up into fries.

    I cook them in a pot of boiling water for 8 minutes.  Meanwhile I pre-heat the oven at 400F (200C).

    and coated a cookie pan I bought from a dollar store with 1 teaspoon of oil.

    When the potatoes are cooked, rinse them in cold water and drain the pot.  I use one piece to brush the surface with oil. I spread the fries on the pan and sprinkle a bit of Italian herbs on top.

    Put both the chicken and the fries in the oven for 20 minutes.  Flip the chicken and fries and bake for another 15 minutes. The chicken should be done.  Serve with vegetables, bread etc.

    If  the fries are not yet crunchy, they might need another 5 minutes. 

    Urban dictionary

  • Fixing Chinesium Connectors

    06/09/2020 at 14:22 0 comments

    It seems that some of the cheaper Chinese parts are up to snuff when it comes to metal and plastic. This is the usual cheap connector that came off aliexpress.

    I went into a few issues with the connector.  These connectors are made with multiple smaller parts and the riveted together. The problem is that the white piece of plastic spacer can deform under heat from soldering.  As a result, the ground ring can spin around and make poor connection.  Older more reliable connectors use phoenic and can survive the soldering.

    To make the matter worse, the plating on the connection has some serious solderability issue unless you use an aggressive resin and/or file off the plating. 

    I use my trusty center punch to punch a hole on the side.  The Chinesium is soft enough that the punch pieces through the outer layer and pinch into the ground contact.  This stops it from spinning around and make a reliable air tight connection.

    For the coaxial power plug, I sometime have to use the center punch on the rivet too as they loosen up easily after soldering.

    The next common problem is the recycled plastic housing cracks for exposure under UV or something.  For that, I made a DIY one out of PVC jacket from old cables with a bit of superglue.

    That thick one is probably from the old SCSI 1 Centronic era.

    Here is the housing from those indestructible jackets. The connector side is simply screwed into the jacket.

    I made a shim out of cardboard on a couple of the connectors because the "Ring" wasn't making proper connection to my PC motherboard audio connector.  It worked for my other 3.5mm connectors, so it could be an edge case of mechanical tolerances.