https://www.cocoacrumbs.com/blog/ Recent content in Blog on Cocoacrumbs Hugo -- gohugo.io en Sun, 06 Oct 2024 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2024-10-06-building-a-nextcube-replica/ Sun, 06 Oct 2024 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2024-10-06-building-a-nextcube-replica/ A few months ago, I stumbled on a NeXT Computer Replica - Raspberry Pi Case from Nina Makes and I printed one of my own but for a Raspberry Pi 4 which required a different back STL file to properly fit. I found this remix here for that. The mini NextCube replica (with a Raspberry PI 4) next to an old 17 inch LCD screen. Using PINN I installed 2 OS’s on the Raspberry PI. https://www.cocoacrumbs.com/blog/2024-09-28-preventing-usb-wakeup/ Sat, 28 Sep 2024 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2024-09-28-preventing-usb-wakeup/ Recently I bought a Logitech MX Anywhere 3S mouse. Since my Bluetooth connection is a bit flaky (my PC is under my desk and plenty of metal is in the way) I prefer to use it together with the supplied Logi Bolt receiver USB dongle. That works like a charm, right out of the box. However, when I put my PC in hibernation or sleep, it woke up, a few seconds after it went to sleep… https://www.cocoacrumbs.com/blog/2024-05-22-meet-dondertje/ Wed, 22 May 2024 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2024-05-22-meet-dondertje/ Georges is now 2 months at his forever home and really became a beautiful cat. But I felt he does feel a bit lonely so I decided to find a little friend for him. Georges being FIV+, he or she needed to be FIV+ as well of course. Somewhat unfortunate, but it’s still easy to find cats who are FIV+ infected and I ended up again at Kat Zoekt Thuis where I found Georges two months ago. https://www.cocoacrumbs.com/blog/2024-03-26-meet-georges/ Tue, 26 Mar 2024 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2024-03-26-meet-georges/ I always toyed with the idea of taking a second cat into my house. Unfortunately, Minou wasn’t very open to that idea since she preferred a more solitary life. Minou fought very hard to recover from her latest illness but unfortunately Minou lost the last battle. With Minou gone, my house felt empty and soulless and I very quickly picked up the idea again to search for a new cat in my life. https://www.cocoacrumbs.com/blog/2024-03-24-passing-away_of_minou/ Sun, 24 Mar 2024 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2024-03-24-passing-away_of_minou/ Always having had a weak health, the last infection was too much for you. I hope you found Molly in heaven who you always searched for every evening since she passed away. She is dearly missed. https://www.cocoacrumbs.com/blog/2023-06-14-getting-the-sd-card-to-work-on-nuttx/ Wed, 14 Jun 2023 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2023-06-14-getting-the-sd-card-to-work-on-nuttx/ Executive summary: It was a hardware problem. In a previous blog post I mentioned that reading an SD Card didn’t work for me when using NuttX. So, I started a long debugging session again but I couldn’t find anything that could point to something wrong. I then switched between the AgonLight and the Z20X computer and I noticed that the error message was different. While Agonlight returned error code 19 (No such device), the Z20X returned error code 22 (Invalid argument). https://www.cocoacrumbs.com/blog/2023-06-09-running-nuttx-on-the-agonlight2/ Fri, 09 Jun 2023 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2023-06-09-running-nuttx-on-the-agonlight2/ Warning: Before you get to enthusiastic… There is no integration at all with the VDP. This is alpha code and for experimenting only! Bernardo Kastrup very kindly provided me with a beta version of the AgonLight hardware. It seemed only logical to try out Nuttx on the AgonLight(2) as well. And this turned out to be surprisingly easy now that I got NuttX working on my Z20X computer. Setup of the AgonLight(2) The AgonLight(2) loaded with the current state of the NuttX code talks via UART1 at 57. https://www.cocoacrumbs.com/blog/2023-06-08-running-nuttx-on-the-ez80/ Thu, 08 Jun 2023 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2023-06-08-running-nuttx-on-the-ez80/ So, now that we finally have a binary, the rest is trivial you would think? Right? Running out of RAM only project I found this in one of the README files for the hello project I compiled in the previous blog post: hello: This is a minimal “Hello, World!” program that runs out of RAM. It is a small program that is really useful only for testing the bootloader. https://www.cocoacrumbs.com/blog/2023-06-07-building-nuttx-for-the-ez80-on-linux/ Wed, 07 Jun 2023 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2023-06-07-building-nuttx-for-the-ez80-on-linux/ Let’s do a few more episodes on the eZ80, “I don’t like Windows.” and “Why do you want to do/know that?”. This time I will try to get NuttX run on an eZ80. What is NuttX? Taken from the NuttX home page: NuttX is a real-time operating system (RTOS) with an emphasis on standards compliance and small footprint. Scalable from 8-bit to 64-bit microcontroller environments, the primary governing standards in NuttX are Posix and ANSI standards. https://www.cocoacrumbs.com/blog/2023-05-06-passing-away_of_molly/ Sat, 06 May 2023 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2023-05-06-passing-away_of_molly/ After an unequal battle against maggots and despite the best efforts of the doctors at the dierenkliniek UGent, Molly passed away on May 6, 2023. She is dearly missed. https://www.cocoacrumbs.com/blog/2023-04-28-using-zilog-zds-ii-on-linux/ Fri, 28 Apr 2023 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2023-04-28-using-zilog-zds-ii-on-linux/ Picking up my series about the eZ80, “I don’t like Windows.” and “Why do you want to do/know that?” again, I decided to see if I could get the ZDS II running on Linux. This actually turned out to be rather easy, with the right hardware… Installing ZDS II under Wine Since ZDS II is only available for Windows, we need a way to let it run on Linux. Luckily this is rather easy using Wine. https://www.cocoacrumbs.com/blog/2023-01-27-getting-started-with-the-olimex-ice40hx1k-evb/ Fri, 27 Jan 2023 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2023-01-27-getting-started-with-the-olimex-ice40hx1k-evb/ Taking a break from my series about the eZ80, “I don’t like Windows.” and “Why do you want to do/know that?”, I decided to take a look at FPGA’s to see if they could be used for my retro projects. More in particular in creating video. A few weeks ago, @lockfarm@twtr.plus pointed me to the iCE40HX1K-EVB dev board which is an incredibly cheap (15.95 Euro at the moment of writing) little FPGA board, including 512KB of SRAM. https://www.cocoacrumbs.com/blog/2023-01-01-reading-zilogs-lod-file-format/ Sun, 01 Jan 2023 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2023-01-01-reading-zilogs-lod-file-format/ Continuing my series about the eZ80, “I don’t like Windows.” and “Why do you want to do/know that?”, I decided to see if I could make sense of the LOD file format produced by the Zilog tools. Although an Intel HEX file can be produced by the Zilog tools, an Intel HEX file is pure binary and doesn’t contain any debug information. Debug information is present however in Zilog’s LOD file format as a simple HEX dump as in the above picture shows. https://www.cocoacrumbs.com/blog/2022-12-05-experimenting-with-the-ti-cemu-ez80-emulator/ Mon, 05 Dec 2022 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2022-12-05-experimenting-with-the-ti-cemu-ez80-emulator/ Update: Two weeks after posting this blog post, I got a friendly message from Adrien Bertrand. Turns out, there are various projects that use the CEmu core directly. They’re only a bit hard to discover. Two examples are: ez80sf runez80 So, more places to get inspiration from on how to use the CEmu core in your own eZ80 projects. Goals Although the Zilog ZDS II tools do contain a emulator for the eZ80, it only runs on Windows. https://www.cocoacrumbs.com/blog/2021-12-28-experimenting-with-the-llvm-toolchain-for-the-ez80/ Tue, 28 Dec 2021 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2021-12-28-experimenting-with-the-llvm-toolchain-for-the-ez80/ Goals Although the Zilog ZDS II tools do their job, they definitely show their age. The main bottleneck is the C Compiler which is stuck at C89 making compiling modern C code painful if not impossible. Even when modern C code is C89 compliant it’s still no guarantee to compile (a good example is LUA). The C compiler is rather slow as well. A while ago I discovered someone wrote a Z80 family (including ez80) back-end for the LLVM/Clang compiler (for the TI84 Cemu project). https://www.cocoacrumbs.com/blog/2021-10-25-nuttx-on-the-stm32f769-disco-board/ Mon, 25 Oct 2021 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2021-10-25-nuttx-on-the-stm32f769-disco-board/ A few blog posts ago, I documented how I created a Linux System for the STM32MP157F-DK2 board. It wasn’t such a pleasant experience. Although tiny compared to desktop or server Linux Systems it’s still huge and consumes a lot of resources just to be able to run. You also get quickly lost in all the packages and scripts that let everything work together. One doesn’t get the feeling you can understand the system as a whole anymore and when something goes wrong, a lot of head scratching is only the beginning of the journey of getting it fixed. https://www.cocoacrumbs.com/blog/2021-10-22-gameduino-3x-on-z20x/ Fri, 22 Oct 2021 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2021-10-22-gameduino-3x-on-z20x/ Having had some hands-on experience now with the SSD1963 display I was somewhat disappointed in the performance. That should not have surprised me since there are a lot of pixels to be moved around with 24 bits colour depth. That’s roughly 1 MByte of memory that needs to be addressed with a humble 8 bits CPU. Even when it would run at 50 MHz, optimized assembly code is required and tricks to get the optimal results. https://www.cocoacrumbs.com/blog/2021-10-16-building-the-st-linux-distro-for-the-stm32mp157f-dk2/ Sat, 16 Oct 2021 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2021-10-16-building-the-st-linux-distro-for-the-stm32mp157f-dk2/ This blog post details how you can build and flash the ST Linux system to a SD Card. Pre-requisites Make sure you have the repo tool installed. It wasn’t on my Manjaro Linux distribution of the host PC and it isn’t available via an easy sudo apt-get install repo for Ubuntu yet (because it wasn’t converted to Python 3 yet). Repo is a tool built on top of Git. Repo helps manage many Git repositories, does the uploads to revision control systems, and automates parts of the development workflow. https://www.cocoacrumbs.com/blog/2021-10-15-building-a-linux-distro-for-the-stm32mp157f-dk2/ Fri, 15 Oct 2021 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2021-10-15-building-a-linux-distro-for-the-stm32mp157f-dk2/ As an intermezzo, something totally different this time and the complete opposite of the retro chips adventures of the last few months. Discussing future projects with the author of the Z20X computer triggered my interest in the STM32MP1 chips from STM. This has 2 Cortex A7 cores (running at 800 MHz) and a Cortex M7 on board. STM also has 2 evaluation boards for them for not too much money: https://www.cocoacrumbs.com/blog/2021-07-02-dec-vt100-enclosure/ Fri, 02 Jul 2021 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2021-07-02-dec-vt100-enclosure/ Now that my terminal works, it’s time to put it into a nice enclosure. And what better enclosure than a replica of the DEC VT100 terminal? After all, this is the terminal that introduced the famous ANSI terminal codes which are still in use today. After a bit of searching I found useful documentation giving me the dimensions of a DEC VT100 terminal. On Aliexpress I found a nice 8" LCD display in a retro 4:3 ratio and with an VGA interface board. https://www.cocoacrumbs.com/blog/2021-07-01-ssd1963-on-z20x/ Thu, 01 Jul 2021 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2021-07-01-ssd1963-on-z20x/ SSD1963 interface code for the eZ80 based Z20X computer A minimal set of routines to initialize the SSD1963 LCD Display Controller in combination with a 7" LCD Display as used by the Z20X computer. Inspiration has been taken from the UTFT Library. Currently, this library allows the following: Initialize the SSD1963 LCD Display Controller for a 7" LCD display. Set front/background colour. Clear the screen (black background). Draw horizontal, vertical lines and rectangles. https://www.cocoacrumbs.com/blog/2021-05-25-hello-world-on-z20x/ Tue, 25 May 2021 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2021-05-25-hello-world-on-z20x/ Intro Since quite some time now, I’ve been intrigued by the Zilog eZ80 which is a successor of the well known Z80. While the eZ80 remains binary compatible with the Z80 it does have some interesting extensions like a flat 24 bits address space (no ugly 64k segments!) allowing to address up to 16 MByte. More info can be found on this Wikipedia page. If you search a bit, then you can quite a few hobby projects using the eZ80. https://www.cocoacrumbs.com/blog/2021-05-20-retro-vga-terminal_part_6/ Thu, 20 May 2021 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2021-05-20-retro-vga-terminal_part_6/ Wrapping up This project is by no means finished (it never is ;-) but so far it works pretty well for me in combination with my RC2014 set up (a SC203 Modular Z180 Computer Kit for RC2014 extended with a Compact Flash Module for CP/M RC2014 Computer). But there is no doubt there are still bugs lingering around. There is no real, solid specification of the ANSI/VT100 escape sequences and unfortunately parts are left open for interpretation. https://www.cocoacrumbs.com/blog/2021-05-19-retro-vga-terminal_part_5/ Wed, 19 May 2021 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2021-05-19-retro-vga-terminal_part_5/ The set-up screen The set-up screen is the only part of the code that is written in C and for this I implemented a very minimal windowing like look and feel (the code is nothing to be proud of though and contains lots of repeated code that could be cleaned up). The set-up screen is activated when you give the terminal the famous three finger salute (i.e. ctrl-alt-del) which brings you with an empty blue screen and a simple menu bar on top. https://www.cocoacrumbs.com/blog/2021-05-18-retro-vga-terminal_part_4/ Tue, 18 May 2021 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2021-05-18-retro-vga-terminal_part_4/ Software Development Writing the code for this terminal really teleported me back to the 1980’s. Luckily with the convenience of quickly erasable NOR Flash memory instead of UV erasable EPROM’s (which would have added 30 minutes or so to every debug cycle). My development cycle starts with writing the assembly/C source code on my Linux PC. Then use the z88dk development kit to generate the binary code. I copy this binary code to a Windows VM to program the NOR Flash using the, probably well known, TL866II plus programmer. https://www.cocoacrumbs.com/blog/2021-05-17-retro-vga-terminal_part_3/ Mon, 17 May 2021 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2021-05-17-retro-vga-terminal_part_3/ Setting up the 6845 Setting up the 6845 involves filling in 16 registers so that the 6845 can generate the correct timing signals for the desired resolution. The available data sheets provide more information on how to calculate the needed values. But since that’s a tedious process, I decided to write a small Python application that could calculate those values for me which you can find below and which was surprisingly accurate. https://www.cocoacrumbs.com/blog/2021-05-16-retro-vga-terminal_part_2/ Sun, 16 May 2021 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2021-05-16-retro-vga-terminal_part_2/ The hardware The design I came up with probably contains few surprises and is inspired by various designs that are floating around on the internet. The complete schematic for the VGA Retro Terminal. Chips used For the TTL chips, the familiar HC or HCT family can be used. There is only one exception. The 74F163 really needs to be from the F family since the HC/HCT version can’t handle the 25. https://www.cocoacrumbs.com/blog/2021-05-15-retro-vga-terminal_part_1/ Sat, 15 May 2021 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2021-05-15-retro-vga-terminal_part_1/ Overview After a long hiatus, which is easily explained as I’ve been working on my most complex project yet. And even more nostalgia I’m afraid… For the last few months I’ve been working on creating an old fashioned video terminal (circa 1980’s) using chips of that era as well (I inherited a ton of TTL chips when my work decided they didn’t need their small electronics lab anymore.). It’s my first digital project in decades and it might still be a bit rough around the edges (my Z80 skills aren’t what they were used to as well I’m afraid). https://www.cocoacrumbs.com/blog/2020-09-04-romwbw-and-linux-how-to-copy-images/ Fri, 04 Sep 2020 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2020-09-04-romwbw-and-linux-how-to-copy-images/ Intro More nostalgia… A few weeks ago I bought the, RC2014 compatible, SC203 Modular Z180 Computer Kit for RC2014 kit on Tindie which uses the Zilog Z180, 512K fast static RAM and 512k ROM (loaded with ROMWBW). To this I added a Compact Flash Module as well for mass storage. With these components it’s possible to create a CP/M compatible system (just add a terminal) running on real hardware of that era. https://www.cocoacrumbs.com/blog/2020-09-01-airplay-receiver-with-pi-zero-w-and-elektor-audio-dac/ Tue, 01 Sep 2020 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2020-09-01-airplay-receiver-with-pi-zero-w-and-elektor-audio-dac/ Intro A few years ago, Elektor Magazine had an interesting DAC project with high end aspirations based on the Burr-Brown (now Texas Instruments) 1794 DAC for a modest price. I bought one and although it sounded very good indeed, it never got used very much. Mainly because it was clumsy to use for me (and lacking a proper enclosure). It was slow (maybe it’s better with a Raspberry 4 now), the touch screen is too small for me (and being of the resistive kind instead of capacitive, not very responsive neither). https://www.cocoacrumbs.com/blog/2020-08-25-runcpm-on-linux-and-arduino-due/ Tue, 25 Aug 2020 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2020-08-25-runcpm-on-linux-and-arduino-due/ Intro I got in a nostalgic mood lately, thinking about the long gone days when I made a Z80 slave CPU for my BBC model B computer and ported CP/M 2.2 (and later ZCPR3) to it as well. Me, decades ago, with a BBC model B and home build Z80 slave CPU (grey box at the front) at the CP/M user group stand of the yearly HCC gathering. RetroComputing seems to be on the rise as well and quite some kits are offered to bring back the computer experience of those long gone days. https://www.cocoacrumbs.com/blog/2020-08-21-tpa6120a2-based-headphone-amplifier-emi-filter/ Fri, 21 Aug 2020 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2020-08-21-tpa6120a2-based-headphone-amplifier-emi-filter/ What is an EMI/RFI Filter? I found this definition on the website of Radius Power: EMI Filters, or electromagnetic interference filters, also called RFI Filters or radio-frequency interference filters, are an electrical device / circuit that mitigate the high frequency Electromagnetic noise present on the power and signal lines. The high frequency noise is generated by a variety of electrical and electronic devices such as motors, electronic controls, power supplies, inverters, clock circuits, microprocessors, appliances, electronic devices etc. https://www.cocoacrumbs.com/blog/2020-08-20-tpa6120a2-based-headphone-amplifier-take-2.5/ Thu, 20 Aug 2020 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2020-08-20-tpa6120a2-based-headphone-amplifier-take-2.5/ Intro Despite the fact that the headphone amplifier really sounded very good (it’s incredibly fast making my headphones sound more like electrostatic headphones), I wasn’t really happy with the measurements I made with the QA401 Audio Analyser. Now that I have a bit of holidays I decided to see what was wrong and what I could do to improve things. EMI filter The obvious place to start with (since it seems I have power related distortion) was adding a EMI power line filter. https://www.cocoacrumbs.com/blog/2020-08-01-tpa6120a2-based-headphone-amplifier-take-2/ Sat, 01 Aug 2020 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2020-08-01-tpa6120a2-based-headphone-amplifier-take-2/ Intro After the successful prototype around the TPA6120A2 headphone amplifier I wanted to build something that could easily be used day by day on your desktop or next to your listening seat. I.e. having a nice enclosure, preferably with a build in power supply (I hate those wall-warts). Hence a take 2 of the design where I also took the opportunity to try out some new things. Overview This time the design started with the enclosure I choose for the headphone amplifier. https://www.cocoacrumbs.com/blog/2020-04-20-rotary-volume-control/ Mon, 20 Apr 2020 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2020-04-20-rotary-volume-control/ Intro I’m the lucky owner of a Devialet Expert Pro 250 (which started as the D Premier many moons ago) driving a pair of Martin Logan CLX Art. (Yes, it’s as good as the many raving reviews say. If you have to chance to buy one, don’t hesitate). But what has this to do with this blog post? Well, one of the nice things of the Devialet is its remote control and more specifically, the way they implemented the volume control. https://www.cocoacrumbs.com/blog/2020-04-01-audiophile-grounding/ Wed, 01 Apr 2020 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2020-04-01-audiophile-grounding/ Audiophile grounding Every serious audiophile knows that properly grounding his equipment is of utmost importance to obtain the best possible sound quality. Of course companies have realised this and offer their own, very expensive, solutions. However, it can be a lot simpler, better and above all, a lot cheaper. For the price, commercial solutions certainly don’t give you much ground. You may be lucky to get 1 kilo of ground for your hard earned cash. https://www.cocoacrumbs.com/blog/2020-03-20-cnc3040-part-4/ Fri, 20 Mar 2020 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2020-03-20-cnc3040-part-4/ A new spindle for the CNC 3040 Another problem I encountered with my cheap CNC 3040 was the cheap spindle. First problem was that it started vibrating (a lot) at certain speeds. Another problem was the higher than expected run out (i.e. rotation inaccuracy which occurs when the tool is no longer aligned with the main axis). The consequence of a higher than expected run out is that the traces you mill away from a PCB are much wider than expected and there will be less copper left (or even none) for the actual PCB track. https://www.cocoacrumbs.com/blog/2020-03-11-cnc3040-part-3/ Wed, 11 Mar 2020 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2020-03-11-cnc3040-part-3/ Milling PCB’s Now that everything is working properly, armed with a fresh set of blank PCB’s and plenty of CNC mills it’s time to try out if machining a PCB is feasible. First test - Loudspeaker filter The PC loudspeakers I build can improved a little with an optional notch LCR filter in case you would find the drivers overly bright sounding. QUCS simulation of the LCR notch filter. The schematic is so simple that I didn’t need a PCB layout application to design the PCB layout. https://www.cocoacrumbs.com/blog/2020-03-01-cnc3040-part-2/ Sun, 08 Mar 2020 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2020-03-01-cnc3040-part-2/ The CNC controller After a lot of searching, and being totally new to CNC milling, I decided to go for a commercial solution and finally settled for this: Mk3/4 controller with enclosure and accessories Although not cheap, this package offered about everything I would need (e.g. the software also included measuring the warp of a PCB and adjust the gcode program accordingly so that the cutting depth is equally deep everywhere). https://www.cocoacrumbs.com/blog/2020-03-01-cnc3040-part-1/ Sun, 01 Mar 2020 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2020-03-01-cnc3040-part-1/ A bit of history - A small series about my CNC adventure. Once I decided to pick up my electronics hobby again (around 2017) I had to think on how to make printed circuit boards (PCB). Breadboards are nice for experimenting but at a certain time it would be nice to have something more permanent on a PCB to build in a nice case. In my youth this was done by either: https://www.cocoacrumbs.com/blog/2019-12-16-new-workhouse/ Mon, 16 Dec 2019 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2019-12-16-new-workhouse/ Now that all of my Mac’s are starting to have reliability issues, it’s time to lookout for a new workhorse. Not that long ago, that would have simply meant a new Mac. Unfortunately for Apple, they have nothing to offer that appeals to me. All laptops have an unusable, unreliable keyboard which is an immediate NO. The new MBP 16" reverts the keyboard back to the 2015 model but keeps the other negatives (e. https://www.cocoacrumbs.com/blog/2019-12-08-tpa6120a2-based-headphone-amplifier/ Sun, 08 Dec 2019 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2019-12-08-tpa6120a2-based-headphone-amplifier/ Since I was so impressed with the performance of the TPA6120A2 I decided to build a more finished product which you can find in a later blog post TPA6120A2 based headphone amplifier - Take 2 Intro A couple of months ago I got intrigued by a glowing review of the Sony DMP Z1 Digital Music Player. Their conclusion was that the headphone amplifier section seemed to be worthy of the $8. https://www.cocoacrumbs.com/blog/2019-10-22-knobbi-and-simba/ Tue, 22 Oct 2019 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2019-10-22-knobbi-and-simba/ I got a new set of photos today of Knobbi & Simba in their new home. They’re 7 months old already. It’s always nice to see they’re doing well. Time sure flies. Knobbi & Simba I Knobbi & Simba II Knobbi brushing up his literary skills. Simba sunbathing. Knobbi demonstrating advanced yoga. Knobbi & Simba binge watching. https://www.cocoacrumbs.com/blog/2019-09-30-stm32-blue-pill-and-black-magic-probe/ Mon, 23 Sep 2019 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2019-09-30-stm32-blue-pill-and-black-magic-probe/ Intro I got interested lately in the stm32 range of micro-controllers. It’s amazing what you can get these days for only a few Euro’s. One of the more famous ones must be the Blue Pill that gives you an STM32F103C8T6 (32 bits Cortex M3) running at 72 MHz, 64KB Flash and 20 KB RAM (compared to the 8 bits controller running at 16 MHz, 32KB Flash and 2KB RAM of the Arduino Uno). https://www.cocoacrumbs.com/blog/2019-07-22-kittens-first-day-out/ Mon, 22 Jul 2019 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2019-07-22-kittens-first-day-out/ Hello World The kittens are 4 months old now and had their first peek of the outside world through the windows. Their mother, Molly, wants to be outside as well and seems to be quite interested in the tomcats that walk outside. Luckily we finally could sterilize her a few weeks ago otherwise we would end up with a new nest of kittens in no time. But since she stays very shy we don’t know if she will return back if let her out. https://www.cocoacrumbs.com/blog/2019-04-27-sunbathing-kittens/ Mon, 22 Apr 2019 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2019-04-27-sunbathing-kittens/ Almost 5 weeks old now and they already start exploring their surroundings. And they definitely like the sun. Enjoy. . . . . https://www.cocoacrumbs.com/blog/2019-04-10-hello-world-kittens/ Wed, 10 Apr 2019 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2019-04-10-hello-world-kittens/ Hello World! Kittens are 3 weeks old now and are taking their first steps. . . . Shy mother cat is not happy with all the attention for her kittens. https://www.cocoacrumbs.com/blog/2019-03-18-discovering-that-the-cat-is-a-she/ Mon, 18 Mar 2019 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2019-03-18-discovering-that-the-cat-is-a-she/ My feral, rescue cat (I named her Molly in the meantime, after the late cat of my parents) is extremely shy and in the past weeks I barely saw her. The only way you would know a cat is in the house is because food is disappearing while the litterbox is (rapidly) filling up. However, I soon found out that Molly is a she. Monday morning around 6 AM, I heard faint meowing… Running downstairs to the living room I found her, behind the curtains, giving birth to her second kitten. https://www.cocoacrumbs.com/blog/2019-02-27-taking-a-feral-in-house/ Wed, 27 Feb 2019 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2019-02-27-taking-a-feral-in-house/ Taking A Feral Cat In House. When visiting my mother in her apartment I noticed a cat was living in the underground garage of the building. The underground garage. Not the best place to live, even for a cat. Asking around, it turned out that this cat must have been living there for at least a year. Surviving on food left behind from a compassionate neighbor and somehow didn’t dare to go out (not surprising, since the garage looks out on one of the busiest streets in Ghent). https://www.cocoacrumbs.com/blog/2018-05-15-preparing-the-receiver/ Tue, 15 May 2018 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2018-05-15-preparing-the-receiver/ Now that we have a nice enclosure, time to put everything inside. This time I used a Arduino Uno. For the display, I opted for the well known 32 by 8 dot matrix display, with MAX7219 drivers. At the back, a DHT22 humidity and temperature sensor will be placed and the 433 MHz receiver module. To round it of, an infrared receiver will be placed at the front for the remote control. https://www.cocoacrumbs.com/blog/2018-05-14-making-a-nice-enclosure/ Mon, 14 May 2018 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2018-05-14-making-a-nice-enclosure/ For the enclosure I wanted something special and not some boring metal or 3D printed box most projects end up in (if at all). For this I found inspiration with DIY Perks on YouTube. First job is making a mold. Luckily, having a CNC mill, this is easily done (once you’ve decided how big you want to have the enclosure). Otherwise, it will take a bit of manual effort to saw the pieces to measure. https://www.cocoacrumbs.com/blog/2018-05-12-preparing-the-sender/ Sat, 12 May 2018 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2018-05-12-preparing-the-sender/ Going wireless Since it’s a bit hard to get a dedicated wire into my house just to transfer the measurements to where I want to see them, I decided to try out a wireless solution. I ended up using the very inexpensive 433 MHz RF modules for Arduino which seems to work well for me since the signal only has to cover a distance of a few meters. On the other hand, the sender will be located below ground level and there is a metal lid above it as well that can block the signal. https://www.cocoacrumbs.com/blog/2018-05-11-getting-electricity-to-the-rainwater-storage-tank/ Fri, 11 May 2018 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2018-05-11-getting-electricity-to-the-rainwater-storage-tank/ Getting electricity to the rainwater storage tank. Since an Arduino will be inside the rainwater tank, I will need some electricity there as well. I could exclude using batteries since an Arduino isn’t exactly low power and I needed to power some sensors as well. I have an electrical cable running through my garden to provide a garden shed (that still needs to be constructed)) with electricity. So, that seems ideal. https://www.cocoacrumbs.com/blog/2018-05-10-rainwater-storage-tank-levelmeter/ Thu, 10 May 2018 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2018-05-10-rainwater-storage-tank-levelmeter/ How it started. I finally moved from an apartment to a house. That also meant, I suddenly had a garden to take care of. The first year was spend with cleaning up the ground. There was plenty of construction material leftovers from the construction company. And a lot of weed. Every evening I cleaned up a small area of the ground with a sieve sifting out stones and weeds up to 30 cm deep. https://www.cocoacrumbs.com/blog/2016-09-16-book-shelves/ Fri, 16 Sep 2016 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2016-09-16-book-shelves/ With the HiFi furniture being sorted, time to look into some acoustic damping, aka bookshelves… Since I do have a lot of books, this seemed like a good opportunity to try out if they could be used to reduce sound reflections from the wall behind my seat as well. The design I used looks a bit like the HiFi furniture I made earlier. So of I went again to the local woodshop and load the car with the needed planks they cut for me. https://www.cocoacrumbs.com/blog/2016-09-03-hifi-furniture/ Sat, 03 Sep 2016 00:00:00 +0000 https://www.cocoacrumbs.com/blog/2016-09-03-hifi-furniture/ I bought my house casco. Which basically means I have to do the finishing all by myself (saves quite some money). I camped for months in my sleeping room while finishing the other rooms in the evening after work. To avoid I would slowdown in finishing the rooms, I kept the living/listening room for last. L shaped living room before I. L shaped living room before II.