MrPix

Very exciting.

https://www.rocelec.com/part/TEXTISLMH1251MTX-NOPB [Edit: nevermind, minimum QTY: 50 - even though they offer pricing for 1-24 and 25-49)...

The LMH1251 is available from main sources for $5 or less. Shop around. Instead of an ATTiny (33c) consider a Greenpak (50c) - it has multiple internal timers, highly configurable discrete logic, and there's a couple of other functions it could do too. It also has some configurability. If you went with some Greenpak family models, I'd be willing to program as many as needed for free, and make them available to whoever at cost price.

When Matthew releases the MKII he plans to open source the MKI - and that might be a more 'satisfactory' option - I would certainly spend the time to redesign the board using more higher level techniques (components both sides) to make it more general. Until then (might be years) this work is important and I look forward to designing an open board for the winner.

Are you taking off the signals from the 9928 and disconnecting those pins from the coleco board? Or are they also feeding the coleco board still? Components on the coleco board would have an effect on driving your system if they're still connected.

To be fair to questioner, that is $12.50+tax to the doorstep. You might consider the 50 cents to offer a small PCB with no functionality other than to be that shape and offer a nice finish with your product name and website on the silk layer. You'd save your customers a bunch of hassle, and if they didn't want to advertise they could reverse it, and/or paint the back to match their case. I suspect people would love to give you a couple of bucks extra to not have to pay $12.50+ to mod a part that still needs painting to match anyway... Just a thought.

I just snagged a 100MHz Rigol MSO1104Z for a screaming good price. When I opened the box, all the optional extra features were already permanently enabled. not even trial licenses! It's already seen battle. Sweet deal for an excellent scope.

I come from the 68K world, so it is quite different.

Shame on you I have it figured out. The DRAM refresh is in a hidden cycle within the normal Z80A bus cycles, so it's "free" in the timing sense. It's something I can safely ignore.

I’ve designed a standard header that is really compact and will go on my multi-card. It will take expansions, and they can stack. So in future I don’t need to redesign the whole card. Just a new daughter card to upgrade the main card. I hope to include two of these headers so future options are easy to add. It also means people don’t need to buy things they don’t want, so if they already have memory they can skip my memory card and save a few bucks.

Made some progress: I've split the RAM off from the MIB card as it takes up too much space and restricts flexibility. It's now a separate daughtercard. Very clean and neat. Just waiting on prototype PCBs.

This had to be the case or we wouldn't be having this conversation

Well that's interesting. I also notice the slew rates on this circuit are a bit slower than on the previous one - which might feed into the narrow pixel problem...

Chances of large gatherings going ahead in a month seem pretty slim. Not trying to be a downer, but don't buy tix now. If things get worse, but the event is NOT cancelled, you'll be able to get some super cheap flights and hotels.

My PCB designer is straining against the leash to be on the winner!

The 250 should fall back to PIO mode if ATAPI isn’t supported. Weird.

Well, it’s simple then. I’m a SMD friendly, low cost open hardware builder. I don’t have a huge profit motive and I like making self install assemblies. I’m happy to supply them to installers at close to cost price - I just need to cover costs, warranties and a bit towards equipment. PS: pulled the trigger on a MSO1104 with the 16 channel DSO section and all the keys came free Very impressed with your screen caps compared to my old workhorse. Only missing feature on my wishlist was CANbus decoding, and it turns out to get that is a $1000 increase in cost and getting a 2000 series.

Since you're doing the heavy lifting on this, do you want to design, build and sell these yourself? Or are you looking for someone with SMD capability to do that bit of the heavy lifting? It just seems fair and right that since you're doing the research for us, you should get first say in what happens next

A small, low power SRAM of recent manufacture should be able to hold contents safely for 20 or 30 years off two CR2032 or similar primary cells.

Since it's blue, and Nobody Cares About Blue(tm) would the expedient thing to do be to add a slight DC offset/bias to it, then use the VR to dial it back in?

Daft question, but if you swap the RGB signals around, does the blue negative follow the signal or stay on that line? Since you haven't mentioned a fast signal diode, I'm assuming you already know that isn't an option. What's your thinking?

PM me and we can talk.

As an example, I just opened a new request on github for you. It is a request to add the ability to update or load sketches to the ATmega via SD card. The primary goal of this is to allow people to download a file and copy it onto the SD card, then simply plug it into the unit and start it, without having to confront the Arduino IDE - which some people find a bit confusing or intimidating. My secondary goal is that it would allow me to eliminate about $6 of components from the board I want to make. If I do not have to support a USB port, a whole bunch of components go away. I can preprogram the QFP ATmegas on my programmer, and then they are able to self update from the SD. Little steps like this are what let me keep costs low for people buying my stuff. They can only happen by talking with the code creators and hoping the feature gets implemented. But if it doesn't, that's okay too - I can just buy the $6 of parts per board and pass on the costs to what are really your customers.

The Arduino Due is based on the ARM Cortex M3, the Atmel SAM38Xe. It costs the same as the Arduino Mega 2560. Not at all. I think you're mischaracterizing me as much as you feel I'm mischaracterizing ADE. I think it's awesome. I made three speculative requests, hoping for a pleasant discussion about the benefits, risks and implications of adding them. All of the requests were added after some thought. I decided to not put forward eight other requests because they would be change for change's sake. I requested you consider support for a different screen than 1602 LCDs, because they are slow and clunky, and often difficult to read except from one angle. I submitted this request after considering that you support a common and consistent module that has the LCD and tactile switches, making the system more modular. What I was proposing was a switch to a common OLED display driver group, allowing much clearer, crisper and faster updating displays. I also saw you already had support for analog/capacitive touch in your code. So I made this request, and hope you are considering it. I requested support for a simple rotary controller for up/down selection. This was suggested to me independently by two people. Really, it requires very little support, and would add maybe 5 lines of code and use two or four bytes of SRAM, depending on how you implement it. I was hoping for a discussion about how people interact with the menus. I thought that even if you didn't adopt the request, the discussion would reveal something of your thinking. Unfortunately, your dismissal of the idea was so brusque that it revealed nothing except impatience at the request. I requested support for a second SD slot. I thought that having the ability to copy images between SDs, without having to use an outside machine like a PC, was a real boon. For those who want two SD slots, it's the difference between building one or two systems (or buying $260 instead of $130 of overpriced ready-make kit...) When you declined this and said "do it on a PC" I had mixed feelings about it. Yes, it's more convenient if that's how you like to do something. But it is also a negative, in the same way that the inability to format DDPs on the Adam is a negative. If I want to duplicate an image on a PC or a Mac, I have to unmount the SD card, walk over to the PC and mount this SD card, dig through and find the right image, copy it to the desktop, insert a new SD, copy the image to that, then take it back to the Adam to verify that it copied and works on the Adam correctly. It's just a huge waste of time. But, you know, people can buy two ardunos and two LCDs and have plugged in bits covering their desk getting ever bigger and more clunky because it doesn't make sense to YOU to support a second SD slot. I have not claimed ADE is unreliable. The code is quite stable and rock solid. It's the shaky stack of Arduino and display and SD slot with level shifters and a couple of resistors and.... and sometimes, when you push the tactile buttons it causes the screen to glitch or reset, or the SD momentarily gets disconnected... In a properly assembled system this is much less likely. In a single board custom system this simply won't happen at all. I even made a suggestion regarding this, to add support for a Keyes remote control, so people could simply activate the buttons without touching the main unit. Again, dismissed without explanation, but instead with a snarky comment about keyboards and joysticks. I don't even know what they have to do with this. For me, the irony of this is that I posted that I'd prefer to talk with you off the github and bounce ideas around, and you passively declined that approach. That type of casual back and forth tells me a lot more about your ambitions for your project. It's amazing work, the code is well constructed, and you have created an incredibly new utility that didn't exist before. It's just sad that you continually go "oooh, I want people to be able to make this cheaply" and when someone says "I would like to make a custom board for this that would be cheaper than buying the parts separately" you basically cut them off at the knees, apparently in support of the $130 product. So the claim of wanting it to be affordable rings hollow. You literally turned down the person offering to sell a single board comprising everything for less than the cost of the parts. So no, I don't disagree with your design choices. I was trying to supplement your pool of ideas and have a discussion with you. I'm not upset. I'm not mad. I just want to work with you to make this thing cooler, better, smaller, sleeker, and more capable. I'm still hoping you'll reach out to me so we can talk. I'm not trying to be impertinent. I don't think it's cheeky to offer ideas to an open source project. Open source = open ideas. I strongly hold to the ethos that if I have ideas I can either request them and have a nice conversation about the relative merits of the idea, and maybe they get implemented but often they don't, or I can fork the code and create confusion in the marketplace of ideas, a destructive competition that moves nobody forward and doesn't aid the users. My door is always open. I'm coming to you with no chip on my shoulder, a very open mind, and requests that are just that - requests, not demands, not expectations. I just want this to be in people's hands in an integrated manner, for less than the cost of the parts.

I suggested to Kalidomra to shift the target to one of the more capable chips included in the Arduino IDE, with more SRAM, but unfortunately he doesn't seem to like that idea. I have started porting it to ESP32, after already porting it to Arduino Due.