09/15/2019 at 01:47 •
I found a USB meter that might have a STM8 inside along with a 4-pin programming connector. It also have series resistors for the display.
I'll let someone else play with it.
09/13/2019 at 02:29 •
It's Friday just before work day, so I sent it off hoping to beat the weekend.
You know it is a tiny PCB when the postage alone is easily worth $0.95. When the board is this tiny, it could easily fit into otherwise wasted space in a batch.
Oops. flipped the soic foot print. Have to redo more routing. This is why I procrastinate on ordering PCB. When I don't, I miss something.
This is how it would look sitting on a SOIC20 footprint. (Too lazy to make up a soic18). The pads are a bit narrower on the USB meter, but it should hold.
It turns out that I can make a PCB adapter that fits the STM8 to the SO18 (wide) pads. I was going to try to make a flex PCB, but decided to try out the making a Castellated Edges 0.8mm (0.031") PCB instead.
All the GPIO are broken out + 1 pad for the Reset on 0.05" pitch. The pinout is weird as it is a STM8 adapter for the SOIC-18 pin USB meter microcontroller that I have previously wired by hand.
It's going to take may be 3+ week from OSH Park.
It has arrived. Original chip (SOIC-18 wide) vs tiny PCB.
It isn't perfect, but good enough for me. Some of the barrel was removed by the milling. The hole size was 0.0197" (0.5mm) vs size of mill ~1mm.
I taped down the tiny PCB for reflow. I recycled the old parts from the mod.
I think it works well enough. It takes a bit of extra heating to make sure that the solder seeped under the pads as well. (The 2nd pad to the left was peeled off when I did the initial mod. )
I cleaned up the mod wires. I routed Gnd, SWIM and Reset (pad RST) to the programming connector. Some of the solder wicked through the via on the inner pads.
It lights up.
09/04/2019 at 01:11 •
New hack: KW203 modded with a STM8S003.
Sorry no PCB as this was a weekend project. There are some additional component changes etc.
Why? Most generic USB meters do not have sufficient resolution to see low current gadgets. My modded meter has a resolution of 1mA and can easily see the current drawn by the LCD meter (3mA) and my USB serial dongle (10mA). It is a handy tool to have.
07/25/2018 at 04:21 •
I have decided to shut down all my projects and start looking for a new host. I need a break from this place. Here is my new place: http://hw-by-design.blogspot.com/
Only started. Slowly moving my projects there.
Trying to learn new editor and reformatting things on the fly. Editor: major improvement and white background finally.
Been playing around a few days, I think I am getting the hang of things. The editor is a major improvement. Gone are the usual complain/bugs. If I accidentally quit the browser while editing, it saved the copy as draft and I can go back in without missing a thing! Wow. No missing first character or pictures that get deleted when you only meant to delete some text. I guess when a company is specialized on blog hosting, they tend to do that well enough. How long do they take to "try" to fix bugs here again?
I have a lot of control on how I can theme my own web page. Everything is about freedom of my choice/preference. If I don't like the colouring scheme, fonts etc. I can change all that as I am the admin of my own site.
Let's say I have not regret the move so far.
07/02/2018 at 12:00 •
It is another scorching day here on the morning after Canada day.
Nothing like starting the day with ice cream with a dense lump of banana bread. I think I got most of the food groups covered.
One thing about being an adult is that you can make your own rules at home...
To our American friends, we started out party early!
03/13/2016 at 20:49 •
or the longest time, I simply hang those wide rubber bands from my grocery in the kitchen. From time to time, I use a couple of them on my pair of pier to hold things together for gluing.
The collection is now big enough to start making my own rubber band ball.
- Start off with a solid core
- Now time to turn it into a sphere
- At this point, you can make it grow by simply adding more rubber bands.
- Start off with a solid core
03/10/2016 at 22:15 •
I bought a cheap pasta maker on Amazon just to qualify for free shipping for something else. The clamp for the pasta maker was unfortunately on the same side as the crank which kind of put my hand above the stove. The clamp wasn't long enough for the front side of the bench.
So I do what any hacker would do under the situation.
11/11/2015 at 17:13 •
When it comes to procrastination, I lost to the repair works at my apartment. I had to patch up a couple of oversized holes left behind under the kitchen sink before I moved in. The new neighbor on the opposite side of the wall is a chain smoker. :( I have asked them to come in, but it is like supervising socially active teenage and the work quality wasn't up to par.
The proper way of doing this is to use dry wall mesh to act as scaffolding before applying drywall filler compound etc. I am not getting paid for this, so I am using whatever I have on hand - cardboard from soda cracker boxes and hot glue that I rarely use.
I measure the diameter out the large drain pipe with my trusty caliper. I found the old compass I had from high school for the circle! I cut out a slit and the circle with a pair of scissors. The cut out fits the drain pipe perfectly. I used tons of hot glue to glue the patch onto the wall board. I glue over a second piece rotated by 180 degrees over the top to add some extra strength.
For the other hole, I cut out an elongated slot. The two offset cardboards allow me to make some adjustments on the width/length aperture. I glooped the whole thing with ample of hot glue to fill the area between the two water pipes.
I went over the patches with my hot air tool to smooth over the glue and make sure that the glue are melted completely and soak onto the surface. It is not a pretty job, but is better than the unfinished repair work or the attempted Saran wrap by the previous tenant.
I ordered some STM32F030F4 parts from China. They are 16kB FLASH with 4kB SRAM 48MHz Cortex M0 in a TSSOP package for $0.60 US a piece at QTY 10. There are the usual 12-bit ADC, SPI, I2C, USART, timers and a 5 channel DMA!!! At that kind of price point, I wouldn't bother with the regular 8-bit chips.
Also ordered some of the Buck Converter modules. All you need is a couple of bulk input and output caps. Hopefully these should arrive before Xmas.
Canada Post and the Canada Custom are getting slower these days. My ten nRF24 clone modules arrived today. With the SFM32F030, these would make some low cost decent LoT modules.
03/03/2015 at 23:45 •
usb.org - The Official Specs
Cypress AN57294 - USB 101 - An Introduction to Universal Serial Bus 2.0.pdf - Very detailed intro