Atari Lynx sync issue

I have been beating my head against the wall trying to solve this problem for over a year (two years? who knows). I finally have it solved but at what cost?

This is what the video effect looked like, the screen is rolled over.

This is what the screen was supposed to look like. (the ratio is different so the black bars were correct, but the sync seemed to have an issue). This was present on the original screen, and on the McWill screen replacement. I eventually went to the BennVenn screen and it was also present there. It presents on some games as an offset, and on gauntlet’s opening animation as completely jumping around between two seemingly different sync positions. 

McWill IPS showing the same problem, but much more apparent. Now this is annoying, but it’s truly baffling to me as I went through the schematic and found that the entire video path all the way to the video chip seemed fine. 

I thought perhaps there was an issue with the 74hc04, but replacing that didn’t help anything. What even is the issue going on here? Looking at this breakdown of the LCD interface it seems like the CL2(HSYNC) pin is having an issue. I re-checked the entire path for that pin and found no problems. I then went to the extremes of getting a parts lynx2 and swapping the video chips. 

I really wanted to see where the problem was, did it follow the video chip, or the rest of the board. Surprisingly I found that it followed the video chip. That’s unfortunate because getting one of those basically means scrapping a lynx2, but at least I know and I can get it reassembled. Then I start having serious issues with reliability. I get constant problems with the cart not being detected and just no video almost all the time. This is incredibly frustrating, because if I had just taken the second lynx, done the cap kit and power circuit fix, and put in the screen replacement it would have worked fine. Now I have an issue I caused. 

Hoping that I had just fried the ram I pulled those chips, swapped them, tested them, and again, no good. I tried swapping the cartridge connector, also no change. I wash it, scrub it, boil/ultrasonically clean it in straight isopropyl alcohol and nothing seems to work. I removed and replaced the video chip several times, touched up all the rest of the solder on the board, checked the power rails, and even replaced the video connector after suspecting it of causing problems. No go. Well, at the end of that article I threaten to do that to the button connector. 

After buying reproduction button membranes you better believe I did that after plugging it in a total of once and verifying every connection with a continuity tester and a diode check for the LED. Still no go. 

Finally I decided that well, I have had issues with vias in the past causing problems. This is a multi layer board from what I can tell so I don’t know exactly where all the vias go, but I can certainly try to help the connections for all the ones I can’t reach once the chip is back on. I heated and pushed some wire wrap wire through the vias and ran it over to the relevant pads. On the chip I mostly bent down the pins that were not sitting on the wire so it sat kinda the same level on the board. The thing is now the chip doesn’t sit flat and there’s lots of room under it. After soldering it down one pin at a time making sure the solder was just enough to bridge the gap but not enough to short to the next pin over I washed the board. I couldn’t just dunk it and walk away though, isopropyl alcohol de-bonds hot glue. Since I now had a couple blobs of hot glue holding my fragile little connectors together for the video and buttons I had to carefully submerge a little in, take it out scrub it with a toothbrush, and then wash it with alcohol and hit it with compressed air to see if I could get any more flux residue from under the chips. I did that for an hour or so until I thought the whole board was clean. 

All good now. It has never had an issue since then. I went through and moved the LCD over to the shell that I installed the buttons in, and it has been working ever since. Now I just have to explain how I added HDMI to it and the audio auto-switches when you plug in the HDMI cable. 

There were many times in the multiple years long project where I wanted to just give up, buy my way out of the problem and stash this one away to fix at a future date. The problem is these consoles are all expensive and ones that aren’t are hard to find and may have similar issues. I am nearing the end for this one though, I think it’s finally coming to an end. 

[EDIT]

I’m not sure that was it. I have had many days of continued unreliability and no clue what’s causing it. At first I thought it was the crystal that I toasted, then maybe it was the shield I reinstalled… It’s back together now but it exhibits some quirks that I don’t know how to quantify. The screen sync seemed to be the video chip, but this is just bonkers. Perhaps I slightly toasted one of the custom chips when I reassembled it. 

Treatlife SS01 & SS01S modification / repair

This post is largely for my own documentation, but feel free to reference it if you have issues with tasmota or esphome based use cases for these wifi switches. For apparently a little while a friend of mine who implemented these switches has been having them fail in strange ways and I’ve been trying to repair them or figure out the cause. I don’t know what it is exactly, but I’m currently pointing my finger at the TYWE3S modules inside them. I don’t know the exact mechanism, but these off-brand ESP-12F modules seem to be compatible, but have an oddly shorter lifespan. These switches were nice when you could program the existing module inside them and put your own firmware on them to make them actually useful for a completely open source locally controlled home, now they need some hardmodding. 

This is my first successful test setup of a conversion for one of these modules. You can see I have an esp-12 spring pin flasher which saves so much time over soldering wires to these modules to program them and I think it’s nice to have them done first rather than building a pogo pin jug to go on top after. I also have the Cliff Quicktest set up for easy and safe testing of the modules in the target environment. I find that testing esp modules off the intended power supply is important as I have previously not had much luck on some of the VERY reduced cost modules and their knock-off ESP-alikes when I replaced them with esp8266 based modules. I assume the esp8266 takes too much current for some of those products and requires further modding to work. 

This is the setup I worked with until I knew everything was working. I soldered it on those wires off the board because I wanted to be able to easily remove it again since this module got programmed with a firmware that looks for my wifi and the other ones are for my buddy’s wifi and I can’t test all functionality of those at my house easily. I determined the right resistor placement by referencing a chart I have to google every darn time this comes up and I might as well link it here. 

I pulled this diagram from this helpful website, and I put the auto-program one because it’s the more complicated one, but in reality you can replace each of those transistors with a button to ground. After verifying that CH_PD was hard tied to 3.3v I set about adding the other resistors and you get what you see above. I could have tied them hard to their respective voltage rails, but this lets me program them in the future (over serial, I think wifi programming would be fine either way) if I need to without desoldering stuff. 

You can see from right to left I started to optimize my resistor and wire placement for ease of doing eight of these in a row. Having CH_PD be at exactly 3.3v was quite a timesaver. 

I tweaked the orientation of the GPIO0 resistor just slightly to clear the screw, but I didn’t need to. There’s plenty of clearance there. 

The SS01S is a nice, simple module that is relatively easy to understand. I like all the labels and test points. 

The SS01 3-way module is a lot more intense and has to balance all the circuitry of not knowing where 120v power will be coming from next and stay online regardless. It also has much more complicated state monitoring circuitry since it can be on either the line or load side. I’m glad I didn’t have to design this circuit. 

That’s it, they all work now. There is something else I could have done to potentially make this easier. I used ESP-12F modules. There are now ESP-12S modules that have some changes that could help me but are also not well documented even by the manufacturer. 

Here’s the esp-12F, and the recommended operating circuit (like the one I put above). It indicates the use of pull up and pull down resistors to let it operate normally. 

This is from the datasheet of the ESP-12S, and it indicates no outside components needed. That’s cool, right? Well, look at those schematics. They are not absolutely copy-paste identical, but they also do not indicate a configuration that would allow this example circuit to work. 

I found a forum thread talking about the differences and they seem to have concluded that there are 12k resistors on the GPIO0, CH_PD, and GPIO15 lines and that the reset pin functionality has changed in a way to make it not reliable with deep sleep based resets using circuitry developed for the older modules. It seems that a series resistor from the module’s reset pin and the reset pin on the chip itself was removed and is needed for reliable operation. The schematics on the datasheet do not show that resistor as having been removed, so shame on Ai Thinker for posting bad documentation. That being said, the internal pull up of the reset line makes me thing pulling that one up externally isn’t needed as indicated on the Ai Thinker datasheet for the esp-12F module. 

Northstar advantage helper boards

In an effort to make testing/diagnosing boards in the Northstar advantage easier I decided to make a small breakout/pass-through board. 

This board breaks out all the pins on the connector to a header that I sized for a 40 pin IDE cable. I increased the number of ground pins and voltage rails to get to 40 pins, but now you can do the raspberry pi trick of cabling it off to a breadboard to work. Included are also points to connect probes to for each power rail and an associated ground so they’re not all snagged onto the same one. for diagnosing the Advantage power supplies because right now I have two out of the three advantages failing to power up the switcher section of their power supply. 

Here it is in operation. I think it goes without saying, but you cannot run this thing with a card in the top and close the lid. Cards that mount to the back with their connectors will be offset and ones that don’t tend to be too tall and will run into the literal glass tube of the monitor and we don’t want that now, do we. 

This last one is my attempt at a protoboard card. I thought I could boil down the circuitry to the bare minimum to buffer the information to and from the bus while adding some potentially useful features. 

 The power section is super generic. I have filtering caps on all three rails and I have two linear regulator footprints. Those are 7809 and 7909 on the schematic, but they’re generic parts that can be used to regulate the 12v and -12v rails. I was thinking about potentially a 3.3v regulator, but for that part I would either want a switcher to come down from 12v or a linear off the 5v. I don’t know exactly what to use them for, but they’re here. 

Same connectors as on my serial card replica, but this time I broke out all the DB25 pins individually so they could be used for whatever. I like the db25 because it gives a mounting point and there’s already cutouts for it on certain slots. 

This part I’m not so sure about. Here I have the data bus bidirectional, and the direction is selectable which is good. I also have all the other pins buffered unidirectionally which is… probably fine? I think all of them are going in the right direction. The thing I’m not too sure about is chip selecting them all together. Normally when one of these cards is selected from the bus the /select line is asserted, and in my use case that signal is not available unless I enable the entire set of signals. I can do that with the jumper, but then to prevent the card from interfering on the bus I also need additional tri-state buffers on these lines? I should probably just tap the /select line and use it to drive the enables with a single wire jumper. Once the board’s enabled everything else might be alright. The initial test I was going to run was creating a board that I can just change the reported ID, that seems simple enough. When I get that done (and probably a second rev of this card) I’ll post them here on this blog. The current board designs are up with the rest of my advantage stuff on github here. 

Northstar NorthNet research

In my research I found many references to Northstar’s “NorthNet” I still don’t know what the hardware consists of, but I found some references to specs in this Q&A that I’ve reposted on my github here. 

That document goes on to describe NorthNet as having up to 64 users on one bus. That claim is corroborated by this brochure from 1982

Here we see a bunch of information on what software exists for the system and how it’s used. There’s also some technical details about it. 

We see the SIO, PIO, and HD-5 we have discussed before, but also the workstation board and server board. Now we know there are separate boards to do that, and the server uses a workstation board as well and that the server board includes an RTC. We can continue looking around to find a dealer manual talking about how to sell people on these products including NorthNet. 

Here we see that the medium is twisted pair cable. I am not completely familiar with the standards of 1982, but that sounds like CAT3 or something like it. But later in that manual we see this:

What relevance is a ‘tap’ for twisted pair, I would assume something like ThickNet as a physical layer to warrant something called a tap. We also see a repeater, which I don’t know where that would be used in a 1980’s network. Near the end we see part numbers for these boards:

The server and workstation boards are way later than the SIO and PIO, but if they follow the same convention those numbers will be on the copper layer somewhere. Perhaps I could search them to find someone who doesn’t know what they have and it happened to get indexed for me to find it by number. Moving on from there I have a list of all sorts of network protocols from around 1984. 

That’s a lot more technical information, but it looks like by 1984 it is still “Beta Test Only”. An interesting side note, in this case I think “letter quality” printers are ones that use a print element that has characters already formed like an IBM selectric or wheelwriter, rather than a dot matrix printer that had characters made of chunky pixels. I then found a picture on a website archived by the wayback machine picturing the fabled NorthNet card!

That is… not what I expected. That looks more like IEEE488 than twisted pair 64-device long range stuff that can use repeaters. I see some intel chips, but I can’t really make them out. If I assume it’s 488, what do I find for chipsets from the ’80s. 

Here’s what I get when I google “intel IEEE 488 DIP40”. That big plastic package chip looks like it says 8292, if I go into it with that number as a guess, and the ceramic one under it could say 8292 if I squint. The logic chips at the bottom seem to be a SN74LS245N, a SN74LS132N? and a SN74S32N. The bottom one I can’t completely make out, but it seems to have something to do with addressing so if I stared at it and the advantage ID byte scheme I could probably come up with a guess. The top two look the same so maybe 8293? I think that’s what would be required to implement this for the advantage card standard. But is this really the NorthNet card and if so which one? Well the top of the board says AD488, so that satisfies my assumptions there. Hey, wait a minute!

Oh man, I thought I had a near complete set of Advantage boards to recreate but now I find out there was a third party manufacturer making all sorts of stuff that will be even harder to find! Well, this didn’t get me closer to NorthNet, but I now have some good guesses at yet another board I will probably never see in person. 

How to make controller cables out of DE-9 connectors

For a long time video game controllers used similar connectors for their cables. The Atari 2600, the Colecovision and Intellivision, The Commodore 64, even all the way up to the Sega Genesis and the Amiga. These ports are nominally a DE-9 connector, but a standard cable mount connector off of digikey won’t always fit. The D-subminiature standard connectors have little wings on the sides of the port with screws that can be used to keep the connector from falling out of the port. Game consoles that adopt these connectors tend not to use those sort of attachments, partly for cost, partly because disconnecting a controller is better than hauling your console down off a shelf and possibly breaking it. Should you need to build a cable that fits one of these consoles, what do you do?

You simply buy one off Console5. 

This is a joke. Not because Console5 does not have good products, but because if you had time or money to do that you wouldn’t be here with me. Those cables are not expensive, but sometimes international shipping gets to be a killer, or you really need a solution today. That’s the situations I’m covering. 

This is your target, a cable mount DE-9 female connector. This one is new, but you can salvage what you need from old serial cables, just carve away at the rubber molding until you find this. It is made of two sandwiched pieces of metal holding he part we need inside. 

To get at the seam between the metal I like to bend it over, this makes the outside metal of the bend go a farther distance and thus create a lip you can grab on to / pry with. 

Now spread the shell apart here, the two pieces of metal are joined at the holes, not the edges so this shouldn’t be so bad. 

Now, with two pairs of pliers (I recommend both have serrated tips) grab both flaps and pull them apart. 

Now you have exposed the plastic part we want, recycle the steel and move on. 

This is what happens if you go too far. The plastic housing is made up of two pieces and inside are the connector pins. You want to keep those housings together so the pins don’t fall out. That used to be the job of the metal shell, but now we have to do that ourselves so it fits with the molding on the fromt of these consoles. 

This is my epoxy of choice for this task, You can also use jb-weld, hot glue, or probably even super glue, but this is the one I trust most in this scenario to not come apart. Once you have the connector together you need to make sure there’s no extra epoxy on the pins so you can solder to them and none around the connector where it mates to the console. 

This is what mine look like when they’re done. I also wrapped them in some “Self-Amalgamating Tape” which is also known as “Self-Fusing Silicone Tape” or similar. This covers the cone shaped joint between the connector and the cable better than a single diameter electrical tape would and won’t peel off and get sticky like vinyl electrical tape. 

Why does my cable have two ends? that’s because it’s a link cable for the sega genesis. I could have cut some cables off controllers and extended them, but this looks cleaner and I had the parts already. 

Here it is in use, you see how those metal bits wouldn’t let it plug all the way in? That’s the problem we’re solving here. There’s even video of it working here. These are the things you can do with multiple copies of the same console and game (or separate variants of the console and a flash cartridge). 

3d model for small portable LCD monitor

In my travels I came across a at070tn07 LCD display with no controller for it. I don’t remember where it came from but I punched that into google and found a generic driver for it that took composite in. I used that as a composite monitor for a while and it’s not great but it works. It would be much more useful if it were mounted in some sort of enclosure instead of just flapping about. So I did that. 

This is what I ended up with, but how did I get here. Well, I admit I’m still new to 3d design, but I made something that worked and used available parts/fasteners I had so I call it a win. I started with the simple part, the faceplate. 

It’s not a complete rectangle, it has some cutouts for the ribbon and backlight cables. It also offsets the mount so the visible area of the screen is centered in the housing, it it not centered in the metal case. 

Here you can see the offset and original 4 mounting holes. I added more later and we’ll get to that. 

Remember, when you’re 3d printing stuff, fillets and chamfers are free. They look good and help guide in things like barrel jacks. 

Once the faceplate was done I needed some place to mount the electronics. Above you can see the plate that mounts the control board and the knobs. I decided to just stand off the board and glue it down because it’s not that critical and it’s sandwiched in anyway. 

Here is layer 2, it electrically isolates the main board and provides a mounting location for the knobs. I decided to raise an edge by the knob mounts so you can’t see the pins sticking through under the board, but I think that area could be improved if I ever do something like this again. I initially had some mounting hole issues because of assuming some things were parallel when they weren’t and measuring relative to the wrong point on the model. They’re fixed now, but I just cut those posts off and the remaining posts hold it just fine. I also only had 4 holes in the part I actually printed. It’s at this point I found out that the sides bowed more than I liked so for the back model I added holes on the center of each edge to clamp it better. The holes on the real part I just drilled (the threads go into the back part mostly, so it being low infill prints didn’t hurt me much). 

This is the backplate. I added cutouts for the barrel jack and composite input sticking straight out the back because I wasn’t feeling very creative. I also added two 1/4″ 20TPI mounting points. This it pretty much the standard tripod or other sort of mount so if you want to buy anything like a clip, clamp, bracket, or whatever, it’ll probably mount with one of those. I didn’t just tap the hole like I did with all the others, no this one is meant to be screwed and unscrewed a lot so I inserted a regular nut for the threads. To secure that I used the gorilla glue equivalent of e6000 and a plastic cover over top. Now this first one mounts from the inside, so the cover should be completely flat and will help retain the but when it’s glued in. 

Yeah, I forgot that and put a hole in it. That’s ok, just don’t screw it so far in you hit the electronics. The other mount feature is on the back. 

This is a boss sticking out the back that’s also at an angle. If I’d though about it harder I would have had the nut insert from the side so the cover couldn’t just be pulled straight off, but this also doubles as a stand because it’s angled. 

This design has some issues and I consider this one of them. I placed the PCB right at the edge of the model. If I would have offset it back a single millimeter or two I could have printed a cover right up between those two knobs that would have made this look so much cleaner. The second issue is because I drilled the afterthought holes by hand one came too close to the display and couldn’t be used so I have one empty screw hole, but it still holds together very well. I assembled this with M3 hardware and just threaded 2.5mm holes in the model. If you are careful and only tighten it so much it will hold without metal inserts. 

I think even though all these plates meet at a perfectly flat surface that you can see straight between when the plastic is a little wavy, it’s fine. There are things I would change for the next revision, but this one works and will stay like this. Next time I might investigate a flange on each layer to hide imperfections, and consider the mounting features like the nuts a bit more carefully before just hoping it’ll be ok. 

My designs are on github, but I may move some of this stuff to thingiverse or printables or whatever, I just think someone having this old LCD and exact controller board so slim that this is mostly a journey of design, not a design I expect other people to use. 

raspi-WD37C65-hat (PLCC)

Having ordered a number of PLCC WD37C65 floppy controllers for a different project I decided that while I was interested in this one, I wanted to redesign it to use the chips I had. 

This is a complete and blatant rip off of Dr. Scott M. Baker’s raspberry pi floppy controller board. He did all the work in designing it, writing the software to talk to it, everything. All I did was remix it to use a PLCC version of the chip and added a couple other tweaks. Let’s have a look at the differences. 

The first is this signal, it’s only present on the PLCC44 version of the part so I have the option to ground it (what I think makes it behave like the DIP chip version) or connect it to one of the spare GPIO lines on the pi. This is the disk change enable line, along with the disk change line they are new for the version of the chip I’m implementing. Let me quote from the datasheet “In the WD37C65A/B, pins 17 and 40, which were not utilized in the WD37C65, became DCHGEN (Disk CHanGe ENable) and DCHG (Disk CHanGe) respectively. Both are active low. DCHGEN is offered as an option for those designs that used the original WD37C65 part where DCHG did not exist as a direct input into the chip”

Here’s that disk change line that goes directly from the floppy connect to the controller chip. It’s for monitoring the disk drive door to indicate if a disk has been changed. That’s a new feature added, the next one is adding something that I figure should have been there from the beginning. 

this HDL line is on the connector standard, it has a place on the controller chip, but the original schematic for this board didn’t populate it. I did but I left a jumper in case it should have the option to not be connected?

This deviation is just going with the crystal instead of oscillator because it matches the datasheet and I have the parts to do it. 

This last one I took straight from my previous design, it’s for using an IBM style twisted floppy cable and undoing the twist in it. This provision is for convenience, you can always just plug the drive into the other connector on the cable. That being said you could use this controller for multiple drives at once. 

That’s it, that’s all I have for you. I haven’t tried it yet, but the designs are up on github here. 

Ramsey CT-70

I don’t remember where I got this thing but it was TRASHED. the batteries had leaked and corroded the main circuit board so I salvaged what I could and tossed the rest. I saved the enclosure, the front mounted board, and most of the chips inside. When I went to look up what I could do with the chips they were specialized to the point that I think the best use I could put them to is rebuilding the missing bits from this. We have a problem, I need the manual and it’s not online in pdf form or whatever, but I can buy a shitty printout from a shitty scan someone took. 

Welcome to the internet archive, yet another manual. No one should ever have to buy that again unless they want a dead tree version and don’t own a printer. Now that I have the manual what’s in store dor me?

Good, schematics with just enough copier burn to know they’re the real deal. And what else?

Oooh, one layer of the board copper. That’ll be really useful. But what’s this connector for the front panel that’s not documented anywhere. 

Well crud, it looks like I have to trace the remaining board I have, this board art, the other board art, and work out where the schematic breaks and what the spacing those pins are. 

Helpfully this stuff shows up great under a blacklight. After much tracing I came up with this. 

No, not that, that’s a fairly faithful recreation of the schematic. I mean this:

That is the layer that existed, the layer that was missing, and all the spacing set properly to line up with the front panel board I still have. 

It’s going to be pretty packed, but since this was a kit to start with I have a pretty good manual that can walk me through building it. 

And I don’t need a ton of instructions on this one, if you want to know about it you can go read the manual. I haven’t made this one yet, but you can find it here if you develop a need for it before I do. 

Apple Pippin expansion connector

I haven’t even started this board layout, but I do want to post what I have as research material so far. The Apple Pippin is a game console that finally runs doom, and also has an expansion connector on the bottom of it for some very rare peripherals. 

The above is not my board, it’s Apple’s, and it’s not even my picture. This is the less interesting breakout adapter for the Pippin, the floppy drive adapter. The connector on the bottom has signals for the Apple floppy standard (different from everyone else) and other more interesting stuff. This connector was actually already reproduced and is available on OSHPark. You can read about it here (where I got the picture) and here (more detail on the board). The cool thing about this being a standard floppy adapter is that you can use a floppy emulator with it. Not a standard gotek, of course, but they exist. Oh, and if you thought this was unique you can also do this with very early imacs. I have pretty blatantly visually copied down the pinout of the original and verified it against the replica and the signals on a standard apple floppy connector. That’s the part you can already buy though. 

This thing was supposed to have other accessories, and some actually exist. Floppy we know already, but ethernet, SCSI, zip disc, and even this strange magneto-optical drive. The thing is, after looking at all the boards it seems that they all just use PCI-to-blah adapter chips, like PCI to SCSI for the drives. There was even an adapter to a regular old PCI slot. This is a little harder to trace than a simple floppy adapter board though. 

After doing some digging I found this great website mostly preserved on the wayback machine. It has a partial pinout for the XPCI slot as they call it (not to be confused with PCI-X) and it includes all the PCI lanes that I think are needed. After combining that with the floppy adapter I now have a much more complete picture of the Pippin connector pinout. 

I’ve captured this pinout on google sheets here, but I haven’t made a board yet because I am not 100% sure of the pin pitch or key spacing. Conveniently they reused the connector for the ROM board that they used for the expansion header so every working Pippin will have a reference card edge I can measure and model. The list of Pippin hardware projects I have is: ROM board, RAM board, Expansion board. All seem like they are in desperate need, and the Expansion board can even break out into a floppy connector and a PCI passive backplane where you can install whatever cards are supported by MacOS of this era. 

arduino-controlled-tv-tuner

In recent times I’ve come to want a standalone tuner that outputs composite video. This would be really nice because I have good composite monitors, but ones with tuners are not usually quite so convenient or nice. It turns out that this is not a common product to find (most people just use a VCR, but that’s pretty bulky). After looking at the datasheets for some tuners I decided to try to pull one off a tv tuner card and drive it manually. 

This is the HP 5187-4378 C1VA82 Asus PVR-416 Blackbird MPEG II FM TV Tuner PCI Capture Card. It has an NTSC tuner and uses a Conexant CX23880 as a successor to the BT878. The tuner is controlled via i2c and the datasheet is published, but I don’t see it at the same address the datasheet seems to indicate. Based on the datasheet and the board itself I was able to figure out the most probable pins for audio, video, and i2c for this variant of the tuner. 

This design has relatively few components aside from the tuner, arduino, small amp, and connectors. I essentially made a minimalist breakout even for features that I didn’t intend to use like the radio functions. 

To make this a standalone device I have several buttons, LEDs, and one of my SPI 7-segment breakouts for displaying the current tuned channel and possibly volume. I have some code to drive the displays on the github repo with the boards and datasheets. If I get it going you’ll hear about it here in some new entry and a link from this one.