#rp2040

[fontesdev]

Better Keeb

A more presentable version of that 3d-printed mechanical keyboard I did a while ago. Now with 100% more numpad! Not enough of that in the mech keeb scene! First time giving ortholinear keys a go, this... will take a bit of getting used to lol

[adafruit]

Bus Pirate 5 is in stock and shipping now, going fast! 🚌 🏴‍☠️

Bus Pirate 5 is the latest edition of the original universal serial interface trusted by hackers since 2008. We've stocked and loved the Bus Pirate 4 for years and are excited to see the latest and greatest from the minds at WhereLabs.

The Bus Pirate is a RP2040 based, open-source hardware debugging tool that converts simple commands into common bus protocols such as 1-Wire, I2C, SPI, UART, several LEDs and more. Send commands to a chip or sensor and get the response, without writing a line of code.

Bus Pirate 5 Base Kit with Bus Pirate 5 PCB and Enclosure

Bus Pirate 5 is the latest edition of the original universal serial interface trusted by hackers since 2008. We've stocked and loved the

[trainsinanime]

I didn’t think I’d need to say this, but apparently I do:

Don’t use the Raspberry Pi 2040 to build a DCC decoder.

It’s not really wrong, of course, and it gives you ridiculous amounts of computing power, but to get that you need miles and miles of extra components. Like a dozen of decoupling capacitors, an external oscillator, and of course an external flash memory. You can maybe do that sort of thing in H0, but for real model trains, it’s just not ideal. Pick something like an ATTiny or STM32C0 (I’ve done both for different projects): Cheap, just one or two decoupling capacitors, no external oscillator required and no external flash memory needed either.

The versions of the RP2350 with built in memory may be a better idea, once they fix the GPIO issues anyway, but still, there’s the oscillator and just way too many capacitors.

(Some of these concerns may be different if you want to add sound support, which requires more memory anyway. But I’d argue that sound in model railroads is a mistake anyway. I’ve never seen an N scale locomotive that sounds good, it’s all just an annoying expensive gimmick.)

Also while we’re at it, don’t use a cheap standard bridge rectifier. The steep slopes of the DCC signal mandate a really fast rectifier, typically Schottky diodes. This is particularly important when you have RailCom on your layout. You may need four individual diodes instead of one rectifier, but since you won’t need all the capacitors of the RP2040, you still win out in the end (it’s also typically smaller than the rather large SMD standard rectifiers).

This is a call-out post for https://github.com/gab-k/RP2040-Decoder . It’s a useful project, but it’s also far from ideal.

[drdnar]

A Color LCD (part 1)

Many years ago, I pulled an LCD out of a GPS unit from the days before cars and smartphones having navigation features. This LCD is a color LCD with a backlight. It’s a very different technology, and much more challenging to interface to. I can’t even find a proper datasheet for the module.

There are datasheets available for modules with similar part numbers. Based on the circuitry in the above picture, this looks like the closest pinout:

B&W LCD modules usually have a built-in charge pump to generate their needed voltages. Unfortunately, the datasheet also says this module needs those voltages supplied externally, and they’re a bit weird.

VDH: +8.3–+8.7 V @ 3.3 mA

VGH: +16.2–+17.0 V @ 0.23 mA

VGL: −8.35–−8.0 V @ 0.17 mA

VCC: +2.5–+3.3 V @ 0.22 mA (this is actually a normal voltage)

Fortunately, I don’t have to design and build a boost circuit myself; you can Just Buy voltage boost modules easily from many places. Getting a module to generate that negative voltage, however, is a lot harder. But it turns out that charge pump chips are A Thing you can Just Buy on Digikey. Sadly, charge pump chips tend to have fairly low output current capability, so while charge pumps could produce the high voltage for the backlight, it would require several and be kind of awkward.

So last week and this week, I finally sat down and learned enough about PIO on the Pi Pico to produce suitable timing signals for the module.

Great! I have a power circuit, I have logic signals, I have a suitable connector, now to see if I can display a picture. Well, one problem: I haven’t built something to hold the LCD. I don’t have a 3D printer, nor any CAD skills, so tonight’s project is to design in Adobe Illustrator a case for the module made of cardstock.

[adafruit]

Coming soon - RP2040 "Bones" AdaLogger

We decided to take a look back at our RP2040 "Bones" boards, and found that we somehow neglected to make one for SD card interfacing. so here it is! with a micro SD socket, we connect all the SPI/SDIO pins so either interface can be used. We still have space for all the classic "Bones" elements: RP2040 with 8 MB Flash, USB C, battery charging, neopixel and Stemma QT I2C port.

[adafruit]

USB C + HDMI combo panel-mount cable sample 🔌🖥️

We got this nifty panel-mount cable with a combo action: both USB C and DVI/HDMI connectors on both ends. This could be handy for single-board computers like Raspberry Pi's or our RP2040/RP2350 boards with DVI outputs

Wouldn't it be cool if you could display images and graphics from a microcontroller directly to an HDMI monitor or television? We think

Since we're testing our Metro RP2350 with HSTX/DVI output anyway, this is a good time to test the cable out - some things we test with USB C cables: verify it enumerates in all 4 orientations (ya never know) and check it with a USB PD sink that requests various voltages. So far, so good; we'll get some of these into the shop in the next few weeks.

[adafruit]

Coming soon - hippity hoppity here comes a floppity 💾 🐇

We had a quest to do some floppy projects back in 2022 (https://blog.adafruit.com/2022/02/09/refactor-of-adafruit_floppy-for-timer-support-mac-disk-success/) but our eyes were bigger than our BOM - many components we designed into this floppy interface board were not available… but now we're back and it's time to make the bestest floppy archiver/writer/emulator(?)

First is the power supply - we need both 5V and 12V. We tried sourcing split 5/12V supplies but were not successful. so instead we can have a 12V power plug and a 5V ~3A buck converter based on the TPS563201 (https://www.digikey.com/en/products/detail/texas-instruments/TPS563201DDCT/5813458). we've also got a TPS259540 12V OVP chip (https://www.digikey.com/en/products/base-product/texas-instruments/296/TPS259540/28780) to make sure the 12V power supply doesn't get swapped with a 15V by accident. USB C can be used when no 12V is needed.

An RP2040 does all the heavy lifting for floppy interfacing. There's a 16M onboard flash plus an optional MicroSD card, so you can save raw disk flux dumps or 1:1 images. We tossed a 1.3" color TFT that might be useful for status updates. Also, we'd like to enable the ability to do off-line archiving - no computer is needed, and a display is essential.

Right now, we only have standard 34-pin IDC and 26-pin 'laptop' floppy pinouts. But we might look at adding disk ][ as well, since we got some Apple disk reading working. Since we have some silksreen room - the PCB is floppy disk sized but tbh we don't need that much space - we added some adorable floppsy bunny art.

[adafruit]

NES Emulator for RP2040 DVI boards demo 🎮🕹️📺

The original Nintendo Entertainment System remains a popular target for emulation. This project pairs the surprisingly capable RP2040 microcontroller with a super-crisp HDMI display and, if you like, an original NES or SNES gamepad.

NES Emulator for RP2040 DVI Boards

The original Nintendo Entertainment System remains a popular target for emulation. This project pairs the surprisingly capable RP2040 microc