While it’s the easiest way to lay out a simple circuit for prototyping, breadboards are a pain. They are the ultimate kludge; they work well enough, but no one will ever say that a solderless breadboard is the most elegant solution.
[Mahesh] isn’t completely fixing the problems of solderless breadboards, but he has come up with a better way to supply power to breadboards. It’s a project called snapVCC, and it turns a 9 volt battery into a regulated 3.3 or 5 volt supply.
The idea behind snapVCC is simple enough; just add a circuit board to the top of a nine volt and add a voltage regulator. [Mahesh] is using an LM317 adjustable regulator, with a switch to change the output voltage from 3.3 to 5 volts. An LED indicates the output active, and another switch disconnects the battery from the circuit. Yes, it’s very simple and very useful, confounding everyone who is wondering why this project didn’t already exist.
The Intel Edison is a neat piece of hardware, but the connector for the Edison is extremely intimidating and the Mini breakout board is incompatible with breadboards. What’s [Federico], a builder of Internet of Things to do? Etch their own breakout board.
The Mini Breakout board for the Intel Edison is the official ‘minimal’ offering for getting the Edison up and running with a mess of jumper wires and LEDs. While this breakout board handles the USB to UART bridge, power regulation, and exposes all the pins on the Edison connector, it is terrible for prototyping. It’s a 4×14 array of holes on a 0.1″ grid that are hidden underneath the Edison.
[Federico] handled this problem with a copper clad board and a little bit of ferric chloride. He jumped into Eagle and created a breakout board to turn the 4×14 pin grid into a more sensible breadboard-friendly layout.
The breadboard-friendly adapter doesn’t have level shifters, but by using the mini-breakout board between the Edison and the breadboard adapter [Federico] still has the UART to USB hardware and a battery charging circuit. Still, there’s room for improvement and we can’t wait to see what he comes up with next.
Tired of wiring up the power rails and serial adapter every time you build something on a breadboard? [Jason] has you covered. He put his Breadboard Buddy Pro up on Indiegogo, and it does everything you’d expect it to: power rails, USB to UART bridge, and a 3.3 V regulator. Oh, he’s not using an FTDI chip. Neat.
With Christmas around the corner, a lot of those cheap 3-channel RC helicopters are going to find their way into stockings. They’re cool toys, but if you want to really have fun with them, you’ll need to add a penny.
Here’s a crowdfunding campaign for a very interesting IoT module. It’s a UART to WiFi adapter that has enough free Flash and RAM to run your own code, GPIOs, SPI, and PWM functions. Wait a second. This is just an ESP8266 module. Stay classy, Indiegogo.
Mankind has sent space probes to the surface – and received pictures from – Venus, Mars, the Moon, Titan, asteroids Itokawa and Eros, and comet Comet 67P/Churyumov–Gerasimenko. In a beautiful bit of geological irony, every single one of these celestial bodies looks like a rock quarry in Wales. That quarry is now for sale.
Here’s something exceptionally interesting. It’s a browser plugin that takes a BOM, and puts all the components into a cart. Here’s the cool bit: it does it with multiple retailers. The current retailers supported are Mouser, Digikey, Farnell/Element14, Newark, and RS Components.
Want a death ray? Too bad, because it’s already been sold.
We’ve been lurking over at Big Mess ‘o Wires as [Steve] geared up for his 68000 computer build. One of his previous posts mentioned a working breadboard version but we figured it would be a ways off. Surprise, he’s got it working and what you see above took just 6 days of “occasional work” to get running.
The chip in use is actually a 68008 but we remember reading that he does plan to migrate to a 68000 because this one lacks the memory pins to address more than 1 MB of RAM. The trick here was just to get the thing running and he made some common choices to get there. For instance, he grounded the /DTACK in much the same way [Brian Benchoff] explained in his own 68k build.
We’re not sure if his address decoding was a time saver or not. If you study [Steve’s] original planning post you’ll learn that he’s going to use programmable logic to handle the address decoding. But above he wired up 74-series logic chips to perform these functions. On the one hand you know your Hardware Description Language isn’t the problem, but did you terminate one of those wires where you ought not?
Additional tripping points include a bouncing reset pin. Looking at that we’d tell [Steve] there’s a problem with his chip, except that this was his first thought as well. He went the extra mile by building and testing a replica of the reset system. This makes our brain spin… shouldn’t the reset be among the most reliable parts of a processor?
At any rate, great work so far. We can’t wait to see where this goes and we hope that it unfolds in a way that is as exciting as watching [Quinn Dunki’s] Veronica project take shape.
[Peter Bjornx] brings classic microprocessors and modern microcontrollers together with his Arduino bootstrapped 68008 computer. The Motorola 68008 is the 8-bit external bus version of the well-known 68000 (or 68k) microprocessor. A friend gave [Peter] one of these chips, so he built a simple computer around it.
This isn’t one of those clean retrocomputers with every connection carefully planned out and wire wrapped. [Peter’s] created a true hack – a working 68k system on a breadboard created with whatever he had on hand at the time. The real gem of this system is the ROM. [Peter] replaced an EPROM chip with an Arduino.
In the not-so-good-old-days, microprocessors (and many microcontrollers) ran from an external ROM chip. This often was a UV-erasable EPROM. Carefully compiled code was burned into the EPROM with a device programmer. If the code wasn’t perfect, the EPROM had to be pulled and placed under a UV lamp for 20 minutes or so to erase it before it was time to try again. EPROM emulators were available, but they were way too expensive for the hobbyist.
Thankfully those days are far behind us now with the advent of EEPROM and then Flash. [Peter] didn’t want to revisit the past either, so he wrote a simple Arduino sketch which allowed it to act as an EPROM emulator, including address logging via the serial port.
The design still caused [Peter] some headaches, though. His major problem was a classic 68k issue, /DTACK timing. /DTACK or Data Transfer Acknowledge is one of several bus control signals used by the 68k. When the 68k performs a read from the data bus, it waits for /DTACK before it transfers data. The Arduino was too slow to release /DTACK in this case, which caused the 68k to think every read was immediately completed. There is a much clearer explanation of the 68k bus cycles on this Big Mess O Wires page. [Peter’s] solution was simple – a D flip-flop connected to the address strobe took care of the timing issues.
It took quite a bit of tinkering, but the system eventually worked. Peter was able to run the 68008 from its reset vector into a simple loop using the Arduino. It’s only fitting that the 68k program loaded by the Arduino was an LED blinker, everyone’s favorite hardware Hello World.
[Czar] was working on a project with the Raspberry Pi using the MCP3008 analog to digital converter. The surface mount SOIC version of this chip was slightly cheaper, and there’s always a way to make that work (Portuguese, Google Translation). How [Czar] did it is fairly impressive, as it’s a bit more flexible for breadboard designs than a through-hole version, and done correctly, is an extremely sturdy hack.
A few new leads needed to be soldered onto the SOIC package, and for this [Czar] chose jumper wires. This makes each pin easy to plug into a solderless breadboard, and since [Czar] was extremely clever, all the wires for power, ground, analog, and SPI are color coded.
Simply soldering a few jumper wires onto a chip won’t last for very long. To solve this problem, [Czar] potted the entire chip and its connections with hot glue. Probably not the best solution, and a heavy-duty epoxy would have been better, but the current build is more than enough to stand up to the relatively minor abuse it will receive on the workbench.
Umm yeah… this is more like it. The STM32F4Stamp is a project which [Frank Zhao] put together to make his ARM prototyping process more like is was back when everything came in a DIP format. As you can see, it’s just narrow enough to leave one row open on the breadboard for jumper wires.
Don’t get us wrong, we do really like STM’s own Discovery Boards for the hardware they deliver at a very low price. But the dual-row pin headers on the larger versions (all except the F0 variant) make it tricky to connect your peripherals. This is pushed to the point that a large percentage of hacks we’ve seen with the Discovery boards are actually just to make connecting external hardware easier.
You may be thinking that there’s a lot missing from this board, but we disagree. Obviously there’s still a USB port which can be used to power the board via a 3.3V regulator. But since the STM32 chips have a built-in bootloader the USB connection can also be used to flash firmware to the processor. Nice! It’s open hardware if you want roll your own. For your convenience we’ve embedded the schematic after the break, along with [Frank’s] demo video.
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