SMD Apple ][ ROM Replacement PCB - Page 1
Forum section: electronics / general

author: deanclaxton
author_rank: Regular Contributor
timestamp: May 18, 2020, 01:34:40 am
content: Hi all,I built an SMD Apple ROM replacement board for Apple ][, ][ plus and ][ europlus.NOTE : This is not a new design - well I've substituted in the 39SF010A flash chip (most use a 27c256 eprom), but the overall concept has been around a while. This is the first SMD one I've seen though, and certainly the most compact!This board replaces all 6 ROMs on the motherboard - you can leave most of the original ones in the sockets as it will overide them - install the board by removing the D0 ROM plus the 74LS138 to the right of it (position F12), then plug this board into the vacated sockets. It takes up no more space that the outline of the 2 sockets it plugs intoThere is a jumper that allows you to select from 2 different sets of ROMS - Applesoft Basic with Autostart F8 ROM (as per the Apple ][ plus, ][ europlus), or Integer Basic with the non-autostart F8 ROM as per the original Apple ][. If you have a Language Card with the Autostart F8 ROM on it, that will take over from the onboard ROM as per normal.With the Integer Basic ROM set I've included the Programmers Aid ROM.The ROMs used :APPLESOFT D0 - 341-0011APPLESOFT D8 - 341-0012APPLESOFT E0 - 341-0013APPLESOFT E8 - 341-0014APPLESOFT F0 - 341-0015APPLESOFT F8 - 341-0020 AUTOSTART MONITORINTEGER D0 - 341-0016-00 PROGRAMMERS AIDINTEGER E0 - 341-0001-00INTEGER E8 - 341-0002-00INTEGER F0 - 341-0003-00INTEGER F8 - 341-0004-00 NON-AUTOSTARTThis is a handy board to have when troubleshooting a system as you now have a set of known good ROMs - especially given the pin rot that some of the original 40 year old ROMs seem to get (the legs get very fragile and can snap off easily - originals are a 9316 masked ROM and are expensive to replace- original masked ROM sets seem to fetch high prices on eBay).It also allows you to remove all your originals and put them in safe keeping!Here it is installed :

author: TK
author_rank: Super Contributor
timestamp: May 18, 2020, 01:54:15 am
content: Nice board.

author: james_s
author_rank: Super Contributor
timestamp: May 18, 2020, 06:39:41 am
content: Looks nicely done. Are the gergers posted somewhere so people can actually build one?

author: deanclaxton
author_rank: Regular Contributor
timestamp: May 18, 2020, 07:01:51 am
content: Quote from: james_s on May 18, 2020, 06:39:41 amThanks James, I was going to sell them on eBay or direct - just trying to track down some suitable pin headers that wont destroy the original sockets (the ones I have are too big atm @ 0.6mm).

author: ebastler
author_rank: Super Contributor
timestamp: May 18, 2020, 01:44:25 pm
content: Selling Apple ROMs is still a slightly grey area, isn‘t it? Or did Apple (and Microsoft for the Plus ROMs, possibly) release those to the public domain at some point?

author: NivagSwerdna
author_rank: Super Contributor
timestamp: May 18, 2020, 02:26:06 pm
content: Very nice. I have been doing something similar for my PET. What we really need is Batten and Allen BA3760 Dill Leadframe (DIP PCB Edge Clip Pins).

author: David Hess
author_rank: Super Contributor
timestamp: May 18, 2020, 03:03:25 pm
content: Quote from: ebastler on May 18, 2020, 01:44:25 pmThere is no grey area at all; the content of the ROMs will be protected under copyright for decades yet so the only question is whether Apple would object.

author: TK
author_rank: Super Contributor
timestamp: May 18, 2020, 03:14:20 pm
content: In this case the board will only be used by owners of Apple II computers. They have the original Apple product and either the original ROMs got corrupted/damaged or this option consumes less power as you select to replace a specific number of old ROM chips by a new more modern flash chip.I am not a lawyer, so cannot give any legal advise, but that is what sounds like a logical reasoning to me.

author: David Hess
author_rank: Super Contributor
timestamp: May 18, 2020, 04:24:08 pm
content: Quote from: TK on May 18, 2020, 03:14:20 pmMostly it will depend on whether the copyright owner wants to make a fuss about it. It is one thing if the owner of the device makes the copy themselves, which also presents practical difficulties for enforcement, and another if they buy a copy from someone else whether they have it or not.QuoteThe law and courts have nothing to do with logic or justice.

author: TK
author_rank: Super Contributor
timestamp: May 18, 2020, 04:32:34 pm
content: Quote from: David Hess on May 18, 2020, 04:24:08 pmI agree

author: james_s
author_rank: Super Contributor
timestamp: May 18, 2020, 08:21:48 pm
content: An easy way around this is sell the device blank and have the user put whatever ROMs on it they wish, or ask the buyer to send the ROM files they would like programmed onto it when they purchase one.I'm surprised that the hardware is not open source, it could be reverse engineered and recreated from the photos in an afternoon if one was inclined to do so.

author: deanclaxton
author_rank: Regular Contributor
timestamp: May 18, 2020, 08:28:50 pm
content: Definitely a grey area, but I'm just selling the hardware. I do offer a free programming service though, so if the buyer emails me a file full of bits and bytes, I can program the flash chip

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: May 18, 2020, 09:19:09 pm
content: Well done. According to some members what you have done is almost impossible, something like the Apollo missions or building a working nuclear fusion power plant.Quote from: NivagSwerdna on May 18, 2020, 02:26:06 pmDo suppliers carry them? They didn't last time I checked. Maybe if enough people asked for them...

author: deanclaxton
author_rank: Regular Contributor
timestamp: May 18, 2020, 09:26:30 pm
content: Quote from: james_s on May 18, 2020, 08:21:48 pmYes indeed - whilst the SMD version is of my own making, I reverse engineered the schematic from a photo of a through hole version I saw on eBay - well I saw that it used 2 x 74LS138's and spent the next couple of hours looking at the Apple ][ schematic and working out how it would work. I went through a few iterations before it jelled - clever usage of the 2nd LS138 to gate the various signals and enable the chip select on the ROM (the first 74ls138 simply replaces the one you remove from the F12 position on the motherboard - that is normally used to enable the chip selects on the 6 original ROMS (not wired through on my board) plus a couple of other functions which have to remain in place).Original post updated to clarify.I wanted a much smaller footprint than the throughhole versions (I think they may have been around a while?) and achieved that by using a 39SF010A flash chip (14mm tsop). At the time I also had some other boards in at JLCPCB so I thought If I could knock it off quickly I could piggy back it onto the existing order and pay very little for additional freight!Downside of the SMD version is that you need to program the flash chip before soldering it down (though if I added a zero ohm resistor on the WE line, and wired it back to an unused pin then I could make a programming adapter).Anyway - the concept has been around a while using 27c256 eproms - I've just put a slightly different spin on it with SMD. I'd be happy to sell bare board if anyone wants to build one themselves - might look at uploading the gerbers somewhere as well.

author: TK
author_rank: Super Contributor
timestamp: May 18, 2020, 09:41:48 pm
content: Quote from: deanclaxton on May 18, 2020, 08:28:50 pmIf you sell the device un-programmed, how do you expect the buyer to program it without making a time consuming adapter for the EPROM/Flash programmer?

author: deanclaxton
author_rank: Regular Contributor
timestamp: May 18, 2020, 09:43:36 pm
content: Quote from: NivagSwerdna on May 18, 2020, 02:26:06 pmYeah I've been looking into those. My current issue is that 0.5mm diameter pins are likely to damage the original Amphenol/RN sockets that they used on these boards. I need to find a pin header smaller if possible or look at some sort of leadframe pins.Issue is that the "smd" leadframe pins clip around the side of the pcb - on this design that is ok for 2 sides, but the pins in the middle are an issue. I need to find leadframe pins that support through-hole.BTW - the Batten and Allen style pins can be purchased from TE Connectivity in single quantities (B&A is MOQ 500,000 or something crazy).The other approach I'm looking at is a couple of sacrificial dual wipe sockets that are inserted into the original Apple ones, and then the adapter plugged into those. I suspect they may have the opposite problem though - the material is too thin to make good contact with the socket underneath.

author: deanclaxton
author_rank: Regular Contributor
timestamp: May 18, 2020, 09:45:41 pm
content: Quote from: TK on May 18, 2020, 09:41:48 pmYeah it needs to be programmed up front - and we are back to the grey area againI guess thats the upside of eproms - maybe SMD wasnt such a great idea afterall!Perhaps I'll stick to distributing them privately (Psssst! Buddy! Want to buy a ROM adapter?)

author: Bicurico
author_rank: Super Contributor
timestamp: May 19, 2020, 09:47:04 am
content: Hi,Nice job and I don't even own a Apple ][ in my growing vintage computer collection (mainly Commodore stuff).I just want to contribute with these two opinions:1) I dislike it when people ask for FREE software/hardware that someone has done! Especially when the goal was to make some money out of it. Give this man a break! He spent time designing it, got someone to produce the PCB, tested it and is now trying to sell the result. Why is this not worth some money? Why do people think others have to work for free? Plus, if it is THAT EASY, well then do your own Gerber file and publish it for the greater good.2) I don't see Apple complaining about this one. Apple ][ rom's can be downloaded from the internet with the simplest Google search and most Apple ][ emulators actually include the roms! This board does not create a cloned Apple ][ computers nor does it take away ANY business of Apple. This board actually required the ownership of a whole Apple ][ computer, which comes with the required software license anyway. Who cares if the board was pre-programmed or not? Because of its exact motherboard fitting on two sockets simultaneously, it would not work on a cloned version of the Apple computer. I think it can leagally be considered a REPLACEMENT PART, no matter if it contains software logic, since the software already is licensed for any target computer of this board and the board itself is useless if such an Apple ][ computer is not provided. Add to this that a regular user cannot extract the software from the board.My advice to deanclaxton is to sell the unit with peace of mind and without feeling any pressure to make any part of the design public. Yes, you reverse engineered the principle of existing designs from their pictures (hardly illegal to look at a picture and learn from it), but you did not simply clone them. You made a different product and you have every right to claim compensation for your work.Regards,Vitor

author: james_s
author_rank: Super Contributor
timestamp: May 19, 2020, 05:59:43 pm
content: Quote from: Bicurico on May 19, 2020, 09:47:04 amI do just that, I always release hardware that I design as open source if it's something that I think others would actually want. That doesn't mean you give away everything for free, that's not how open source works. Take Dave's uCurrent for example, it's open source, does that stop people from buying them? Doesn't seem to, most people would rather buy a finished, tested product and do just that. Even I was going to do that, the only reason I built one myself is that at the time I went to order one they were out of stock.I promote open source because I believe in the model, I contribute to the community and encourage others to do the same. That doesn't mean a person can't/shouldn't try to sell something they've taken the time to design, but I'm far more likely to support something if the design is available, I just don't have much interest in closed/proprietary products and will choose the open design every time given the option. The OP is of course entitled to do as he wishes, it's his design and my Apple II is working fine with the original ROMs still so it's not something I need anyway.

author: deanclaxton
author_rank: Regular Contributor
timestamp: May 19, 2020, 10:09:24 pm
content: Quote from: james_s on May 19, 2020, 05:59:43 pmTotally understand James - I'm not ruling out releasing the gerbers - I just want to make it as good as it can be before I do so. I've had some great feedback and have a couple of features that I will add to it first, and then re-evaluateNot everyone has a 14mm tsop32 programing adapter - to purchase one is more than the cost of the assembled product (at least the one I purchased certainly was)!

author: deanclaxton
author_rank: Regular Contributor
timestamp: May 23, 2020, 09:06:04 am
content: Respun the PCB to support 8 ROM Images and re-programmability in an EPROM programmer via an adapter (rev was actually increased to 1 on the files sent for production, plus legend slightly updated versus the one below):Also did an external switch board, and gave the project a name.An 8 position rotary octal switch was suggested, and I might swap out the switches for one if I can find one of a decent physical size - most seem tiny.PCB's are on order

author: deanclaxton
author_rank: Regular Contributor
timestamp: July 14, 2020, 05:35:06 am
content: Well this project has really developed over the past month or so. I teamed up with Jeff Mazur (an Apple ][ programming guru), slung a CPLD on the underside and ended up with the following features:1. Same low profile, small footprint as the first board!2. No switches! System boots a menu screen from the ROM at first powerup - all ROM selections are done from the keyboard!3. 16 ROM images including the master boot image!4. All 16 ROM images including the master boot image are user programmablein system!5. ROM-LINK interface to a text ROM board - with text ROM selection through the same menu!6. You can set a default ROM image for both system and text ROM - system menu will time out and boot your default!7. Info (128 bytes) can be stored for each ROM image!8. We've registered the domain theromexchange.com - will be used to share ROM images!The 2316B SPCL Text ROM replacement (connects to the main ROMX board via ROM-LINK interface, so you can use the menu to select text ROMS):There is another version of the text ROM board for pre rev 7 mainboards which upgrades the text capability on the pre rev 7 to that of the rev 7.Proof of concept running in my ][ europlus:Undergoing timing analysis/debug during development:PCB's shown in the Altium renders above are with DHL and I'm hoping to receive them this week! I'll be changing the JTAG header for a TAG-Connect one on the production boards, but hopefully this is it - quite possibly the ultimate ROM setup for an Apple ][/][+...

author: ebastler
author_rank: Super Contributor
timestamp: July 14, 2020, 06:23:20 am
content: Something seems wrong with the images; I can’t see any. (Only in the most recent post, your prior post looks fine.) Maybe some access rights setting on Google Drive? Thanks for checking!Edit: Thanks, working now!Edit again: Strangely, just a few minutes laterallimages are gone, including the ones in the earlier post. Is it just me? (But I see this via two different browsers and devices.) It might be better to attach images to your post than to use links. That way, they reside on the forum server and are going to stay there for posterity, even if and when e.g. you terminate your Google account.

author: ebastler
author_rank: Super Contributor
timestamp: July 14, 2020, 10:24:46 am
content: Well, it it'sthisJeff Mazur you teamed up with, and maybethisguy too, he seems to be more than "just" a programming guru for the Apple ][...Very nice progress on the project! One thing that had me wondering is the "ROM exchange" idea though. Isn't that still a bit of a dicy area with regards to copyright? Obviously there are various sites which host ROMs e.g. for the MAME emulator, but I probably wouldn't want to be the operator for one of these. How do you plan to steer clear of copyright issues?

author: deanclaxton
author_rank: Regular Contributor
timestamp: July 14, 2020, 10:34:58 am
content: Yep - I was a CPLD noob starting out on this project, and Jeff was a huge help there as well! The hardware and CPLD was my domain, but he had a pretty clear idea of what we needed to iimplement in CPLD and in code to pull the whole thing together. Being able to flash ROM's onto the chip from either the menu, or an accompanying disk utility is very, very cool.To be honest I'm not 100% sure on the best way to deal with the copyright issue - the Apple ROM's are everywhere though - even being distributed with emulators!One possible way forward is that we would not directly store the ROM images on the site, but provide a toolset that can fetch the files from elsewhere. Still thinking about that, but to be honest it's the last piece in the puzzle. I'll wait till I've tested the near production boards, then take it from there. At least now the end-user can build their own ROM sets and upload them to flash - some of the responsibility has been passed on.

author: David Hess
author_rank: Super Contributor
timestamp: July 14, 2020, 01:48:11 pm
content: Quote from: deanclaxton on July 14, 2020, 10:34:58 amI blame Disney.