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• Physical Connections and Updates

  Dustin • 10 hours ago • 0 comments

  Random Updates

  With the new job consuming 60 hours a week, plus commute time and extra sleep, I have had very little time to dedicate to any of my projects. This project comes to mind at times, and I wish I had the skill to just sit down and knock it out quickly. I am still learning all the needed skills, so progress is painfully slow. On a brighter note, funding for the project will be readily available in the next few weeks to months, and I could just order everything I need all at once and get started. I plan to order a few more Pi 400 kits. I have my main one, which I still use as my daily driver laptop and Jellyfin server. I am typing on it now. I'd rather not use it for testing. I plan to buy a Pi 400 as a dedicated Jellyfin server, another as a test platform for this project, and maybe even another as a backup, or for a secondary development platform so I can work on 2 projects at the same time. I'll be ordering some bulk SD cards, and setting up a formatting station for managing and backing them up. I currently don't have enough space for so many Pis, as I'm renting from a friend, but I should be setting up a workshop here soon and will have ample room.
  

  OS Support

  I know that it makes the most sense to support the official Raspberry Pi OS, and that's where I'll likely start, but I also want full support for Pop!_OS by System76 as I've found it to be the best daily driver OS on the Pi to date. They're a small, friendly company who I suspect would really enjoy this project, and I might be able to get some official support, even if it's just some advice over email. I use Pop OS on my Pi 400, only switching it out for Raspberry Pi OS to run my Jellyfin server. Once Jellyfin has offical support for Ubuntu 21.10, I'll switch over to Pop OS entirely. I feel that it would make a friendlier experience for kids as well, since the entire OS is geared towards the scientific, engineering, and educational fields. Ideally, the system could be ported to any Linux OS, but that isn't always feasible. I'm sure Windows 11 will continue to mature on the Pi, and I may end up supporting it at some point, but not right away. I can't stand Windows, and will avoid it as long as I can.
  

  Physical Cartridge Connection

  This is a very important aspect of the project to me. I've been thinking about wear and tear for years, but have started thinking more deeply about it as a new maintenance engineer. I watch these industrial machines wear themselves out and fall apart in a matter of hours to days, where most consumer equipment would last years. It's quite the eye opener. With the PiCarts, I want to build to an industrial standard, as I know these systems may end up in the hands or children, with their sticky, maximum-effort hands, and complete disregard for strain relief and longevity. I don't blame them, I just understand them. The biggest failure point I have identified so far is the GPIO pins on the Pi 400. Though recessed, they remain exposed and vulnerable. Plugging and unplugging things to and from the GPIO port also requires a significant amount of force, especially if not done straight on.
  

  I have been really enjoying the magnetic connectors I have on my phone charging cable, as well as the magnetic phone stand I built. I'd like to be able to integrate such a feature into the PiCarts, if feasible, for use with educational systems. The typical hacker will do fine with the regular pins. The matter of being able to short pins still needs addressed. I have been considering pogo pins on the carts, and an adapter that plugs into the GPIO port. I could possibly have the contacts on the Pi side adapter recessed into a PCB, with longer pogo pins on the cart that would fit down into those recesses, and connect when they are safe from the poking and prodding of various objects. This would protect the power pins on the Pi from being shorted. Rare earth magnets in the cart and the adapter could be used to hold the cart to the system, while allowing them to come...

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• Cart Idea: Video Carts

  Dustin • 11/21/2021 at 20:53 • 0 comments

  As a kid, I annoyed my parents to no end making them rewind the same few VHS tapes for me several times a day so I could rewatch things over and over again. It also annoyed me to no end when my favorite tapes wore out and died. Sad times to be a kid. These days, we have far better technology. I was listening to a song by Omnia called "The Well" and really enjoyed the story it tells, though simple. It reminded me of the animated tale of The Deathly Hollows from the Harry Potter movie. It got me thinking about how to get more story time into the world. Then I remembered my project here. I imagined having a cartridge that you could just plug in and it would play videos. You could put anything you want on them of course, but something useful and educational would be best. Unless you're like me and like to binge watch Futurama or Spongebob on shuffle. There would be obvious licensing conflicts with selling copyrighted media, so a blank cart with an SD slot or built in flash memory and the video player software could just be sold.
  

  The hardware would be simple enough and could be a generic design that could be used for media playback of any kind. Headphone jack, media control buttons, perhaps volume control, a "shuffle" button, maybe even a small screen for controlling the software. Another option could be to add a small screen to the GPIO port such as a Pimoroni Hyperpixel 4" display. Being able to watch TV on a tiny display attached to the keyboard and work on a larger HDMI monitor would be quite nice. Also being able to leave the main monitor off, or take the Pi 400 on the road and play media with a tiny display would be great. Such a cart would end up being more expensive than most other carts, as the display itself is rather expensive. Would be well worth it for what I do. I have a Vilros Pidock 400 that turns the Pi 400 into a laptop, but the display uses a fair bit of power and has no brightness control at all, which bothers me at night. Sometimes I wish I could just hit a single button and have something start playing, like a random TV show or movie. Another thought occurred to me: the Pi 400 doesn't have much processing power, and playing media on it will slow it down and may make it less pleasant to use. This could be solved by adding something like a Raspberry Pi Zero 2 W to the cart to handle the actual playback. That would add options to have it stream things from other sources as well.
  

  Possible hardware:

  • Pimoroni HyperPixel 4" Display: $65
  • Adafruit Cyberdeck Hat: $9

  The two pieces of hardware above would be enough to get me started, with only buttons needed. A custom board with buttons and audio output would make up the finished item.
  

  Software wise, I'd either use VLC Media Player for playback, or maybe write a custom program using ffmpeg as the backend. It would be easy to let feature creep take over on this and never get it done. Sticking to the core functions would leave it with play, pause, stop, rewind, fast forward, next, back, and volume controls.
  

  This particular cart will have to wait until I get a few other pieces of the puzzle put together, but it would be something that I would use regularly as I work.The thought occurred to make a version or some sort of cable that would let it connect to a Pi 400 in the Pidock 400 and mount to the main screen to act as a secondary display as well.
  

• SD Card Breakout Board Testing​ 2

  Dustin • 11/14/2021 at 15:13 • 0 comments

  I was able to get the board to stop resetting the entire system by hooking it up to 5 volts. I also finally got the SD0 overlay working and confirmed the pins are configured correctly in software. I was unable to get the card to mount, and no activity light action on the breakout board. I'm starting to suspect there is a hardware problem with this breakout board. The overlay is set up to use all of the data pins of the SD card, not just the two that are broken out on this board. I'm going to order a simpler SD breakout board for the next round of testing. I was very frustrated with the lack of progress on this, but I have the software sorted and am happy with that. I'm hoping to have an SD card working over GPIO shortly after the new SD breakout board arrives. If that's the case, this project can move forward onto the software development stage. As much as I want to skip ahead to hat and start making games and programs for this, I don't want to get distracted and put off the hardware aspect, as it's the most important part. 

  The problem I was having with the software was my own dumb fault. I put the sd0 overlay file in "/boot/" instead of "/boot/overlays". That caused it to fail to load. I was also playing around with different overclock settings and such, which I reverted to the original settings. The pins are now configured properly and the OS tries to mount the SD card over SDIO at boot, but fails and starts the OS afterwards. 

  I still have the 512MB SD flash chip I'm not using. It uses the SPI interface, which I have no idea how to use with the Raspberry Pi OS as a mounted drive. I may just use the SPI interface for saving configuration files and data I don't want the end use to mess with. I'd include documentation and ways to modify it of course. 

  Still many important decisions to make, but progress has been made. The first step after getting the SD card working over GPIO will be performance testing. I need to know just what I can do with this card. I'll start with simlpe benchmarks, then move onto real word testing, such as streaming high bitrate video files from it. Read speed is most important to me for this project. I don't have a working SDIO SD flash chip yet, just the SD card itself. The datasheet for the chip claims class 10 performance, I believe. I will just have to get a similar SD card for initial testing an confirm with the flash chip when I get one working.

• Initial SD Breakout Testing

  Dustin • 11/14/2021 at 13:26 • 0 comments

  A few days ago I started testing with the two SD breakout boards I got. One is a micro SD card breakout board, the other is an SD flash chip breakout board. I got the device tree overlay in place as well as turning on polling so it would check for a card inserted every second. When I boot the Pi up, it gives an error saying device timed out and unable to mount, but that's to be expected as I couldn't physically connect the card to the GPIO. When I hook up ground and power the Pi reboots immediately. I couldn't figure out why for a few days, but I have a theory to test now: Too much current draw. That could be a major problem. I don't believe I had the breakout boards powered directly from the 5 volt pins which can provide far more current than the 3.3 volt pins that were recommended in the document I was following. I have a 5 volt tolerant micro SD breakout board, so I'll start with that. If that works, I'll have a second SD card over GPIO and a working proof of concept for this project. That would be good enough for me to move onto software development. 

  I'm going to post this quick update before I try to hook it up so I don't crash the system again. I'm running the latest Raspberry Pi OS (32 bit) from a Samsung Bar 32GB flash drive on a USB 3.0 port to avoid the corrupted SD cards I've been having trouble with lately. I had a 256GB SD card I was going to use for extra storage and backups on the Pi, but it got corrupted so badly I couldn't save it. Ordering a new 512GB soon.

  I'll post another update soon with the test results.

• Pi 400 Everyday Use Experience

  Dustin • 11/10/2021 at 15:54 • 0 comments

  I've had this for a few days now and really enjoy it for the most part. I have a Pi 400 inside the Pidock 400 as my everyday computer as well as the development kit for this project. It is very good so far. My main issue is with the software. I'm having trouble with OS reliability. It crashes randomly and I haven't had the chance to figure out why. I'll keep using it and try to make this my primary PC. I made the switch to Linux in 2018 or so, and have been using it exclusively since. I hope to do the same with the Pi 400. I don't really need much more from an every day computer. I feel it's worth the effort to figure out how to make it more every day friendly. I do need more processing power for video editing and re-encoding, but I have a minimalistic plan for that as well. I'm considering ordering the Minis Forum HX90. It's a very powerful and portable pc that would handle the heavy work the Pi 400 can't. I can even use the Pi 400 as a keyboard and mouse for it, as well as use the Pidock 400 as the monitor, as it has a standard HDMI input. This would let me use my Pi 400 laptop exactly as I already do, but with a very powerful PC running behind the scenes. I plan to travel the country on a motorcycle soon, and don't want to give up a proper desktop PC or my Raspberry Pi projects. This solves many of my issues all at once.

  Overall I love the Pi 400 and Pidock 400. The keyboard is good enough for me, it's portable and powerful enough for my everyday research and programming, and I love the fact that I have such an interesting and useful laptop now.

• GPIO Audio Output

  Dustin • 11/10/2021 at 15:25 • 0 comments

  As I research and work on this from my Raspberry Pi 400 laptop, I realised that the Pi 400 has no audio output aside from HDMI. That's fine for most use cases, but not all. I would love to have a headphone jack on the Pi 400 for times when I want privacy, to drown out the noise of the world, or to stop from being rude or annoying people. This would be useful for children as well, so parents don't have to listen to the annoying, repetitive sounds that kids seem to love so much. I'm n exception; I spent much of my very young years annoying the hell out of the adults around me. A small onboard speaker would also be useful as well. The headphone jack would be great for listening to music while working as well. I know my headphones won't reach the TV's headphone jack. 

  I'm havng trouble finding a solid way to get a headphone jack working on the Pi400 right now, but I worked 14 hours straight yesterday, so I'll give myself an excuse this time. I could probably buy some sort of HAT for audio output, but I want something I can integrate into the board as a standard feature or add on. I'll do more research on this later and maybe order a few audio boards for testing. I want to keep it all simple and open enough that people could tinker with the audio themselves as well. This reminds me of adding an audio card to a vintage PC. Some didn't have any audio output, or maybe just a beeper. I think it would be quite fun to integrate an audio card into one of these carts. 

  The best I've found so far is  Pimoroni's Pirate Audio Headphone Amp. It's rather expensive at $25, but would give me a good place to start. 

  Another good option, though lacking an amplifier for headphone use is the UDA1334A I2S Stereo DAC breakout board from Adafruit.

  Of the two options I've found, I prefer the simple and cheap Adafruit breakout board. I can learn with that, then integrate the design into a board and add an amplifier chip if needed for headphone use. 

  Good audio is important to me, and I prefer to hear the world through my in ear monitors these days. Mee M6 Pro for anyone interested. My Pidock 400 takes HDMI audio from the Pi 400 and breaks it out to a headphone jack, so I've been quite spoiled by the set up so far. Not everyone is going to have one of them, and I want to see a headphone jack on the Pi 400. I'll put that task on the low priority list and focus on such luxury features after the base memory cart is working. I was curios as to what it would take to get a headphone jack on the PiCarts, and now I have a good idea. I don't have the skills to implement it yet, but I'll get there in time.

• Prototype Hardware Ordered

  Dustin • 11/05/2021 at 00:14 • 0 comments

  I ordered the GPIO extension cable, prototyping hat with EEPROM, SD card breakout board, and SD flash chip breakout board from Adafruit recently. That's just enough to get me a single cart with an SD card socket connected over SDIO and a 512MB SD flash chip connected over SPI. The extension cable is needed so I can connect Pi HATs while my Pi 400 is in the Pidock. I wish I were more excited about all this, but I haven't had the time or energy. When the parts arrive, I'll solder everything together and start testing it out. Software will probably be the hardest part for me. It's my weak point so far. I think there are libraries out there for the Pi to use SD cards over both SPI and SDIO. If so, I'll install them and get started developing a very simple test program to read and write. From there it's just a matter of adding the features I want and creating an easy way of installing the software. I haven't touched Python in quite a while, so I'm sure it's going to take me a while to get it going. I've been playing with Arduino lately, so my C++ is decent enough. I was able to write an entire relay test program for the Raspberry Pi Pico, from memory,on the first try. That was a nice milestone. Let's hope Python comes back to me so easily. 

  More updates soon after the new hardware arrives. 

• New Pi Day: Pi 400 and Pidock 400

  Dustin • 11/03/2021 at 19:22 • 0 comments

  Please pardon the low quality picture. My nice phone is no more, and I'm using my cheap phone. I'm also lazy, so there's that too. 

  I've just gotten this awesome Pi 400 laptop set up, and I love it so far. The keyboard is better than I thought it would be, ad the screen is surprisingly great. I wasn't expecting much from this, but I'm happy so far. I received it this morning, but only had time to unbox, assemble, and pack it away in it's travel case it came with. It shipped with Raspbian Buster on the SD card, so I need to upgrade to Raspberry Pi OS when I get home. The wifi at Panera is dreadfully slow. The Pi itself runs well enough for me and I'm typing this up on the Pi. There's o way I'd want to set up a Pi 4 at a coffee shop, so this is a game changer for me. When I hit the road to travel again, I'll be able to take my Pi projects with me quite handily. 

  I haven't started any of my project work yet, as I want the latest OS ad updates installed. I'll place an order for the new cartridge hardware here soon so I can get to work. Adafruit actually has a 512MB SD flash chip on a breakout board that I can work with. It uses the SPI interface, so is slow, but that's ok. They also have micro SD breakout boards so I can just use an SD card as a substitute for the actual flash chips I ruined trying to solder them. They even have FRAM chips in both SPI and i2C interface options that I can play with. I'll grab one of each of those two boards, a 512MB SD board, an SD card board, and some prototyping boards. That should give me plenty of memory options to work with and covers the three main interfaces I had been exploring for this project: SPI, 2C, ad SDIO. I'll order a GPO extension cable so I can still use Pi HATs with this crazy laptop thing. Another exciting addition to this device is a 3.5mm audio jack for headphones and such. I can listen to my music instead of everyone elses' while I work in public. Can't wait to get the new hardware in. I may order just a few of the pieces today and the rest next payday to be safe. Don't want to be dipping into savings. I had to pick up MORE gloves for work as I keep leaving them on the bed of the tow truck and driving away. It was $60 for 3 pairs of gloves today, which was money for this project. 

  I will be using this Pi 400 with many different SD cards and operating systems. I have a 256GB I'll use with Ubuntu Mate, which will be my main system with all my music and movies on it. Just personal stuff. The card that came with this will have Raspberry Pi OS and be kept stock for development on this project. I'll install Android(Lineage OS) on another for access to my Android games and such if I can get it to work. I'll have another card for retro games as well. I already have a very nice SD card case, just need to fill it up. 

  I could ramble on, but I need more time with this. All I know so far is that I really like it as a laptop, and I love the fact that it's a Raspberry Pi. I think this is exactly what I needed. Plenty more updates to come soon.

• 1GB Prototype Board Also Dead

  Dustin • 11/02/2021 at 15:19 • 0 comments

  I've officially given up on these damn SD memory chips for now. I don't have the skill, patience, or the steady hands to work with them. I couldn't get the adapter board unsoldered from the prototype HAT, and just broke the board and threw it away. I'm so sick of every little thing being such a massive struggle. I hate soldering and don't want to deal with it anymore. I can't justify or afford a desoldering gun right now and my crappy little pump is nearly useless. I'm out around $50 worth of hardware and multiple frustrating hours of work so far. I'm going to order new prototype HAT boards, SD cards, and SD card breakout boards so I don't have to deal with these tiny SD memory chips anymore. I wish there was a breakout board for them already. They're new enough that no one seems to have bothered. I can't physically manage those tiny chips anymore, so I'm giving up on prototyping with them until I can order a custom PCB with them on it. This makes me very sad and frustrated. It all comes down to the loss of my steady hands. I'm turning 29 soon, but I feel far older. Physically overworking my body since I was 14 is taking it's toll on me. Everything is catching up. I've traded most of my youth so far just to survive. I want to get into software and hardware development so I can do something more fulfilling and easier on my body. I'm driving a tow truck to fund my journey into better work, but it's not easy. It makes me so very sad to look back on my life and realize how much of it was wasted. I refuse to waste much more of it though. I will finish this project, even if it means working with SD cards instead of the cheaper and far more interesting SD memory chips during the prototyping phase. 

  I won't have any hardware to work with when my Pi 400 arrives tomorrow, but I still have plenty more work to do. I could just solder jumper wires to an SD card adapter and plug that into the GPIO pins directly for testing if I want. I've got all the parts for that laying around. I think my shaky worn out hands can manage that bit of soldering. I'll still order more hardware for prototyping though. 

  Just got a call and need to go tow a car. Annoying interruption, but at least I'm at a decent stopping point. Let the stupid begin...

• 8GB Prototype Board is Dead

  Dustin • 11/02/2021 at 14:58 • 0 comments

  Well, I tried to solder the 8GB memory chip to the adapter board and failed miserably. My hands shake so badly these days that I just couldn't do it. Two of the pads underneath got bridged and I couldn't fix it. I don't have the tools, skill, knowledge, or steady hands to unsolder the chip and try again. My shaking hands are making me really upset. I've always worked with my hands and they've never let me down until today. I ended up so frustrated and upset that I snapped the board in half and threw it away. I'm not proud of this and I normally wouldn't share such things. I think it's important to share failures though. This one is particularly painful for me as I realize I'm getting older and the damage I've done to my body over the years may be catching up to me. I can hardly solder DIP packages anymore. These SOIC chips are just too much for me. I think I'll just get an SD adapter board and use that for software development until I can get a custom PCB designed and pay someone to assemble the damn things for me. It's the same thing, just a different and more expensive form factor. I want an SD cart anyway to add a second SD card to the Pi over GPIO. Most of my work lately has been big stuff requiring tons of strength, so I didn't notice how shaky my hands have gotten. Maybe my hands are just weak. Thankfully I have one chip soldered and a back up plan. 

  This project is very exciting and frustrating at the same time. I still have to desolder the entire adapter board and rotate it as I screwed that up a while ago. I'm starting to realize that I'm not interested in the hardware assembly anymore. I'd rather design the hardware then write code for the finished device. Once my Pi 40p laptop thing arrives, I'll start learning PCB development and just outsource it all to a fab house and be done with it. I don't really have the time these days to do prototyping myself anyway. Once the snow hits, I'll probably be working 80+ hours a week as a tow truck driver. I'll have plenty of money but no time or energy. I'll happily outsource as much of this as I can to get it done. Maybe I'll outsource the board design for the prototypes as well, just to get development hardware in hand immediately. I have plans to build up a touring motorcycle and live out of that in the Western US, which would free up plenty of time in the future. That might be a year or so away, so I'll just have to outsource what I can now. I'm excited to have endless days to tinker with this. 

  This was a good, but stressful event. I'm out probably $20 worth of hardware, but that's a cheap way to finally be honest with myself and realize I don't want to do this part anymore. 

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