SMC ROM Simm programming

Drake

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Kay K.M.Mods

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Thank you @Drake
Great blue ROM SIMM sticks that @Stephen sells contains a program that he has personally selected!
https://www.ebay.ca/itm/235230996131
Super price, shipped from Los Angeles!

And let's discuss flash other than ROM SIMM in this post!
Examples:
-GAL or PAL on your accelerator board or mother board
-Other ROMs on your vintage computer things
-Flashing programs on your 8-bit computer cartridge's ROM

Drake’s Crucible tutorial video.*Please watch this video before

Project Details, my Blog
https://ameblo.jp/keroxiee1016/entry-12779429924.html

An early tutorial shortly after release. *If not using Crucible
https://ameblo.jp/keroxiee1016/entry-12785559537.html

Tinker Different Post for Crucible
https://tinkerdifferent.com/threads/crucible-for-the-smc-rom-simm.2361/

Special Thanks:
@OneGeekArmy , Author of Crucible and Defender of Our Friendship

Steve Chamberlin, BMOW, He and Keros Mac Mods have a deal at ROM-Inator Resurrections. I consulted with him at the design stage about commercializing ROM SIMM, and he understood. Our ROM SIMM uses the open source Rob Broun disk driver and does not include BMOW firmware, startup sound, or FC8. However, I am deeply grateful to Steve for his understanding and advice.

Rob Braun, Father of all manufacturers ROM SIMM and great genius hacker
http://www.synack.net/~bbraun/classic2.html
 
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Kay K.M.Mods

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Additional information

The following ROMs can be easily created using Xgecu's T48. I'll add photos later.


1, Model: Apple IIe Enhanced ROMs
スクリーンショット 2023-10-11 2.14.58.png
ROM storage location:
https://mirrors.apple2.org.za/Apple II Documentation Project/Computers/Apple II/Apple IIe/ROM Images/

Method:
In order to change the specifications from the initial IIe model to the Enhanced IIe model, you will need to flash and replace the three ROMs.

CD ROM: 342-0404-A
EPROM 27C64

EF ROM: 342-0303-A
EPROM 27C64

CD and EF ROMs will have the Apple ROM numbers above. The EPROM used is 27C64 (2764 is the same), and the capacity is 8KB. For example, ST M27C64A is relatively easy to obtain.

Video ROM includes text characters, so there are various hacked specifications. General US specification is following.

Video ROM: 342-0265-A 
EPROM 27C32

EPROM 27C32 is 4KB. For example: TI NMC27C32BQ and ST M27C32A are relatively easy to obtain.
As shown in Drake's video, first point the EPROM in Xgecu's flasher APP, then point it to the ROM's ".bin" file downloaded above to flash it.

2, Model: Apple IIc ROM4x
*ROM0,3 and 4 are same way

スクリーンショット 2023-10-11 2.14.26.png
ROM storage location:
https://downloads.reactivemicro.com/Apple II Items/ROM_and_JEDEC/IIc/

Project page:
https://github.com/mgcaret/rom4x

Method:
EPROM uses 32KB of 27C256 for the ROM4x. Example: ST M27C256B is relatively easy to obtain, but it is also a discontinued product, so we will use a recycled one. I don’t recommend buying just one EPROM, so buy several EPROMs in case the product is defective. *Many Chinese sellers probably sell sets of 5 or 10 pcs.
As shown in Drake's video, first point the EPROM in Xgecu's flasher APP, then point it to the ROM's .bin file downloaded above to flash it.
*There are two ROM4x .bin files in the above ROM storage location, but there was no big difference no matter which one was used in my experience. Please use a later version just in case.

In addition, to make IIc ROM4x, change the two jumper solders on the mother board. The positions are W1 and W2.
Reference link;
https://www.apple2faq.com/apple2faq...g6dHxvxYdH9SbyCvsA-Zr1-_e0wyenW6WFG-cKSsxj_oM

Tips:
- Compatible EPROMs are available from many manufacturers. In rare cases, the output pin specifications may be different, so please check the data sheet. The EPROM example given above should work well.
- If a pin error occurs, clean the pin with nail file stick, In my case, I stole it from my daughter's makeup box...lol
- In some cases, eBay or Ali sellers, they sells products without erasing the EPROMs, so it is convenient to have a UV eraser available. *It is difficult to erase in sunlight. Fluorescent lights for disinfection are the most efficient. UV LEDs have different frequencies and are often useless.
 
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Kay K.M.Mods

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If you have a EPROM programmer then you may also like this tutorial I made a few years ago which describes how to make ROMs for early compact macs.
Thank you @Stephen , it's very good instructions for the enthusiasts.

In the TL866 generation, DIP42 and PLCC44 ROMs could not be flashed, but in the T48, they are now supported by an adapter. This can flash ROMs such as Macintosh Classic II, 27C400.
D9050FC0-DAC1-46FA-9F78-7C3DE630F30E.jpeg

Even in the case of the TL866, someone has made an adapter that flashes each ROM divided into four parts using a dip switch, so you can use that, but using this may seem a bit cumbersome.
7B7EF253-DF6B-40CB-8714-EA726052EF9F.jpeg
 

retr01

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Awesome instructions! Thank you, @Kay K.M.Mods! :)

Can the Mac be used instead of Windows? Perhaps a Mac program can connect to one of those three ROM programmer devices. If I recall correctly, @JDW and I would stick with Macs instead.
 
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Kay K.M.Mods

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Awesome instructions! Thank you, @Kay K.M.Mods! :)

Can the Mac be used instead of Windows? Perhaps a Mac program can connect to one of those three ROM programmer devices. If I recall correctly, @JDW and I would stick with Macs instead.
There was a way to run third-party apps using Homebrew, but that is a thing of the past. Mac OS changes frequently, so it is difficult to maintain compatibility. Even Homebrew cannot support two generations ago.

Currently, Xgecu's successor programmer, T48, is the mainstream. As far as I know, there is no option other than Windows for this.

However, I think it will be fine if you start virtually Windows10 on your Mac and use these, or install Windows 10 on your Mac.

My recommendation is to have a cheap Windows desktop that you can buy used for under about 70 USD (DELL or HP ...), as I'm sure it will help you in many ways.
 
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JDW

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My recommendation is to have a cheap Windows desktop...
@retr01
Kay does make a good point. And he has kindly given me that same advice in the past too. I certainly do not want to discount the important of his recommendation at all. Even so, I will share my story below and then provide you with your two options.

MY STORY​
I ultimately broke down and bought this T48 kit in May 2024, in large part because I wanted to help out a fellow vintage computer enthusiast in need. That person asked if I could desolder an EPROM from my rather rare MMI 10MB HDD (from my HyperDrive kit) and extract its contents. Ultimately, I turned a blind eye to the high risk of accidentally destroying the drive, in large part because I decided my action would help not only that one person but the community at large too (by way of sharing the file). The ROM dump I made using the T48 is now a Resource here.​
Of course, the T48 cannot be used with a Mac 😭, and I didn't want to eat drive space with Virtualization. And to avoid tainting myself with a PeeSee (correct spelling) at home, I just borrowed one at the office. It runs Windoze (proper spelling) version 8, and the T48 software runs fine on it. The T48 software is reasonably easy to use, at least for me it was, but I have experience programming PIC MCUs using Microchips software (which actually DOES work on Macs), so maybe that's why.​
Folks who can't borrow a Bill Gates Abomination at the workplace may have no choice but to go with Virtualization; and honestly, there's nothing wrong with it if you've got the drive space on your modern Mac for it. (I actually do, but I'm stingy with my drive space.)​
In terms of purchasing low-cost tech on the Dark Side, you probably could opt to buy a cheap "netbook" for the sake of keeping the size small, allowing you to then hide it easily when not in use. You can't easily hide away a large desktop PC.​
I don't mean to tick off the Windows lovers too much. I deliberately poke fun at the PC world because I've always felt Windows to be little more than a bad copy of macOS, and I've been perpetually surprised at how >72% of the planet is addicted to that platform. I've used other people's Windows machines enough to know it's not great. Heck, I even built Windows PCs when I was a senior in high school in 1989, and our electronics class was also tasked with maintaining them too! Yeah, they've made a lot of advances since 1989, but I still feel icky using even Windows 11.

Beyond that, my first home computer was the 128K Mac in 1984 when I was 13. Since that time (for the last 40 years), I've never purchased a Windows PC for my personal home use, nor even ever brought one home. I kid you not. Not being a gamer helps avoid the PC world, I guess. Some may call my never having owned a PC crazy, but others would regard it as genius.​
END STORY​

You have 2 hardware choices on how to flash your SMC ROM SIMM:

1. Buy a cheap PC or use Virtualization so you can use a T48 programmer to flash the individual chips on the SMC ROM SIMM, in conjunction with the four BIN files that the Crucible app generates.

or

2. Buy a ROMmate Programmer v2 (BMOW no longer makes their ROM-inator programmer), then use the v2.0 SIMM Programmer app from @dougg3 (Downtown Doug Brown). Even though you don’t have to use the Crucible v1.1 app anymore with this setup, what’s really neat is that you can still use it, if you want, to change your little Happy Mac icon to something else, then export the four BIN files. Doug’s v2.0 SIMM Programmer app is able to easily flash those 4 BIN files to the individual chips on your 2MB SMC ROM SIMM while the ROM SIMM is socketed in a v2 ROMmate Programmer. You don’t even have to pull out the chips from the SMC ROM SIMM, which makes flashing fast and convenient. On top of that, this setup can flash all of the flashable SE/30 ROM SIMMs sold today (Kero's Mac Mods, GGLabs, BMOW, SiliconInsider, CayMac Vintage, Garrett's Workshop, etc.). So if you have more than one ROM SIMM from different vendors, Choice-2 is really the ultimate choice.
 

Kay K.M.Mods

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@retr01
Kay does make a good point. And he has kindly given me that same advice in the past too. I certainly do not want to discount the important of his recommendation at all. Even so, I will share my story below and then provide you with your two options.

I agree with that point, but I'm not going to get into an argument that has no end in sight lol
Of course My main computer is a Macintosh, it has been 30 years or more.

But you know, in Japan, iPhone market share is 60% now today. As a result, Macintosh's market share increased from 5% ten years earlier to 11%. Apple is more popular in Japan than any other country in the world. *Haha, there is some hope in Japan.

One complaint is that the OS changes with each model change, and compatibility with older OS is no longer maintained. That is roughly up to two generations ago. Support for anything beyond that ends. "Homebrew" also supports the latest OS, but doesn't support OSes two generations old anymore. *which I think is a security issue...IDK
This means that users have to keep their old Macs if they want to use older devices and apps. For example, if you don't want to use the cloud-bound Adobe Illustrator, the last OS you can use with AI will be Mojave.
What I'm trying to say is that if you're using a geeky device, whether it's a Windows or Mac, there are times when you just can't get what you want without having multiple computers.
 
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retr01

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Hi @JDW and @Kay K.M.Mods,

Thank you for sharing your perspective that sometimes, to accomplish specific tinkering goals, you should use a Windows-based machine, whether an actual garbage PC or a shoddy virtual PC on a Mac.

Who knew that Microsoft and Crowdstrike held many flights hostage as recently as about a month ago? That explains. 😄

Hmmm, the ROMmate Programmer v2 is an intriguing option! Even better, the software now works on Apple Silicon Macs. Thank you for letting me know, @JDW!

@Kay K.M.Mods, due to the advancements Apple has made with the Silicon "M" architecture and the upcoming AI (not artificial intelligence, but rather APPLE Intelligence) with the M4 and on, as well as compatibility with M1, M2, and M3 coupled with many security fixes (a lot more!), it has become a more manageable model for major software companies like Microsoft, Apple, Google, Adobe, Autodesk, etc., to switch to the server side. Considering operational costs and profitability with subscription and cloud-based apps and services makes more sense. Furthermore, updates and security fixes are more seamless and quicker, especially since lightning-fast Internet, including Star Link, is available worldwide. With AI, advances should be much more incremental as we move from Industry 5.0 to Industry 6.0.

We have to do what we can for those who still love to tinker with our old computers. Thankfully, it is still possible today.
 
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robin-fo

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Awesome instructions! Thank you, @Kay K.M.Mods! :)

Can the Mac be used instead of Windows? Perhaps a Mac program can connect to one of those three ROM programmer devices. If I recall correctly, @JDW and I would stick with Macs instead.
I‘m not quite sure if this is a helpful answer, but I use my TL866II+ with modern macOS using minipro. Maybe the T48 is also supported..
 

Kai Robinson

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@retr01
Kay does make a good point. And he has kindly given me that same advice in the past too. I certainly do not want to discount the important of his recommendation at all. Even so, I will share my story below and then provide you with your two options.

MY STORY​
I ultimately broke down and bought this T48 kit in May 2024, in large part because I wanted to help out a fellow vintage computer enthusiast in need. That person asked if I could desolder an EPROM from my rather rare MMI 10MB HDD (from my HyperDrive kit) and extract its contents. Ultimately, I turned a blind eye to the high risk of accidentally destroying the drive, in large part because I decided my action would help not only that one person but the community at large too (by way of sharing the file). The ROM dump I made using the T48 is now a Resource here.​
Of course, the T48 cannot be used with a Mac 😭, and I didn't want to eat drive space with Virtualization. And to avoid tainting myself with a PeeSee (correct spelling) at home, I just borrowed one at the office. It runs Windoze (proper spelling) version 8, and the T48 software runs fine on it. The T48 software is reasonably easy to use, at least for me it was, but I have experience programming PIC MCUs using Microchips software (which actually DOES work on Macs), so maybe that's why.​
Folks who can't borrow a Bill Gates Abomination at the workplace may have no choice but to go with Virtualization; and honestly, there's nothing wrong with it if you've got the drive space on your modern Mac for it. (I actually do, but I'm stingy with my drive space.)​
In terms of purchasing low-cost tech on the Dark Side, you probably could opt to buy a cheap "netbook" for the sake of keeping the size small, allowing you to then hide it easily when not in use. You can't easily hide away a large desktop PC.​
I don't mean to tick off the Windows lovers too much. I deliberately poke fun at the PC world because I've always felt Windows to be little more than a bad copy of macOS, and I've been perpetually surprised at how >72% of the planet is addicted to that platform. I've used other people's Windows machines enough to know it's not great. Heck, I even built Windows PCs when I was a senior in high school in 1989, and our electronics class was also tasked with maintaining them too! Yeah, they've made a lot of advances since 1989, but I still feel icky using even Windows 11.​
Beyond that, my first home computer was the 128K Mac in 1984 when I was 13. Since that time (for the last 40 years), I've never purchased a Windows PC for my personal home use, nor even ever brought one home. I kid you not. Not being a gamer helps avoid the PC world, I guess. Some may call my never having owned a PC crazy, but others would regard it as genius.​
END STORY​

You have 2 hardware choices on how to flash your SMC ROM SIMM:

1. Buy a cheap PC or use Virtualization so you can use a T48 programmer to flash the individual chips on the SMC ROM SIMM, in conjunction with the four BIN files that the Crucible app generates.

or

2. Buy a ROMmate Programmer v2 (BMOW no longer makes their ROM-inator programmer), then use the v2.0 SIMM Programmer app from @dougg3 (Downtown Doug Brown). Even though you don’t have to use the Crucible v1.1 app anymore with this setup, what’s really neat is that you can still use it, if you want, to change your little Happy Mac icon to something else, then export the four BIN files. Doug’s v2.0 SIMM Programmer app is able to easily flash those 4 BIN files to the individual chips on your 2MB SMC ROM SIMM while the ROM SIMM is socketed in a v2 ROMmate Programmer. You don’t even have to pull out the chips from the SMC ROM SIMM, which makes flashing fast and convenient. On top of that, this setup can flash all of the flashable SE/30 ROM SIMMs sold today (Kero's Mac Mods, GGLabs, BMOW, SiliconInsider, CayMac Vintage, Garrett's Workshop, etc.). So if you have more than one ROM SIMM from different vendors, Choice-2 is really the ultimate choice.
James - have you tried this for the programmer?


Ben Eater (https://www.youtube.com/beneater) uses the TL866 with his Mac via terminal and this program, should work on the T48 as the github code states:
  • Experimental support for Xgecu T48 programmer
 
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retr01

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Hmmm. Having a chart of what works and what doesn't would be helpful. Perhaps one of us can create a new thread to discuss this further since this thread is rightfully related to SMC's SIMM and programming products.
 

JDW

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@retr01
:) Here's the "what works chart" in hard-to-read text form:
The official Kero's Mac Mods programming solution for the 2MB SMC ROM SIMM is the T48 programmer in combination with Crucible v1.1 (macOS software app), as per that info showing on the SMC ROM SIMM product page. As I mentioned earlier though, the alternative is the Doug Brown v2 Programmer sold by CayMac Vintage as ROMmate (the only one of its kind currently sold), used in combination with Doug's SIMM Programmer app v.2.0.​

Crucible was created for people who buy the SMC ROM SIMM, and it's technically naughty and wrong to use it with another vendor's ROM SIMM. However, if you have an SMC ROM SIMM, you can use Crucible to generate the 4 BIN files and then use your ROMmate programmer to flash them to the SIMM; which means, you don't even need a T48 programmer. But those who own a T48 and not the ROMmate can now flash the individual chips of the SMC ROM SIMM with their Mac thanks to the new info kindly posted above today, and which I will now describe below.

@robin-fo & @Kai Robinson
Thank you for the tip! I also wish to thank @pocketscience too because I had totally forgotten he mentioned it to me at the end of July this year via PM! Ack!

Here's a nice article about MiniPro GUI (for Mac), as it pertains to the TLS866II+. This is a good place to start.

Next, I found this video extremely useful in getting GUI for MiniPro installed on my Mac. It is rather troublesome (versus a normal macOS installer), although it was perhaps easier for me than it will be for some of you though because I already had HOMEBREW installed on my Mac.

I was able to get my T48 to connect and read some PIC MCUs I have. Yipee! I only performed READs and not WRITEs, but it seems to be working. Overall, the UI isn't nearly as nice as the full blown Windoze app, but hey, it's Mac support for the T48, and who can really complain about that?

@Kay K.M.Mods
There's now a T48 software solution for people who want/need/have a T48 and who (like me) stubbornly want to use Mac software with it.
 

JDW

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CayMac drools
I emphasized that the true creator of the ROM SIMM Programmer (the v2 hardware currently being sold as "ROMmate") is Downtown Doug Brown in my earlier posts because he is technically not associated with CayMac, other than having given them permission to move forward with the sale of his programmer, and having worked with them last summer to hash out the details. I was privy to all that discussion because I made a video on the subject of ROM SIMMs and Programmers, which pertained to ALL ROM SIMMs, including SMC and the Garrett's Workshop SIMM as well.

Gamba and Jeff Walther (aka @trag ) technically laid the groundwork for custom ROM SIMM creation way back in 2003, but it was Doug's excellent programmer in 2011 started all this ROM SIMM fun. Without that Programmer hardware, I wonder if we would even had ROM SIMM enjoyment today. So thank you, @dougg3 ! And a big shout out of thanks also to Rob Braun who did the critically important work of modifying a Macintosh IIsi ROM with a ROM Disk Driver that allows booting from the ROM, similar to a Macintosh Classic. That work on the base ROM file made software like Crucible possible.

It was in 2016 that BMOW, with permission from Doug, starting selling a very slightly modified variant of Doug's handiwork. Sadly, in 2019, Steve Chamberlin had to halt sales of the BMOW Programmer due to difficulties sourcing parts. In was in that knowledge that Kay Koba, with great insight (which I hold in the highest regard), decided try something new in 2023 that would not rely on a vintage Mac vendor selling, and then suddenly discontinuing, a dedicated SIMM programmer. Kay opted instead for the T48 Programmer. The T48 and similar will ALWAYS be available because it doesn't rely on vendors in the vintage Mac community to produce it, and many more buyers exist for a general purpose programmer than a ROM SIMM programmer. So Kay really did make a good decision here. I have high praise for his decision to do that.

But the fact remains that Doug's ROM SIMM Programmer hardware is highly regarded by all, and I do not wish to allow that truth to be diminished by personal sentiments about particular vendors. Yes, we have different vendors who are rivals. And some vendors commit sins a tad differently than you and I do. Shocking but true. But Doug's v2 Programmer is currently only sold by a single vendor, in part because nobody else was willing to take on the burden of selling it. Selling and keeping customers happy is hard work.

This thread is focused on the SMC ROM SIMM and the Programming of it, which includes the incredible Crucible software authored by @OneGeekArmy (and thank you for the excellent videos about that, Drake!) and the T48 programmer (which I now see can work with macOS — yeah!). But info about a second programming solution is also helpful, especially because it provides another solution for owners of the 2MB SMC ROM SIMM. More options is always better for the end user.

My hope is that this discussion will work to spark more interest in the SMC ROM SIMM, which I think is a great product going forward.
 

Kay K.M.Mods

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Yea, I knew Minipro, as I mentioned before, if you are installing Homebrew for the first time, you should be using a newer MacOS (at least two generations older). I mentioned this a little further down in the thread. So, if you are using MacOS before Monterey, it will be a bit of a hassle...
 
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