Another IIci ROM hack

[dougg3]

Oh I'm sorry! Of course. Anybody who is interested in a rev 2 SIMM, shoot me a PM. The cost will be $29 including priority mail shipping to the US (I'm using their flat rate boxes which are about $5). So the SIMM is $24 and shipping is a little over $5, but I'm rounding to $24+$5=$29 and calling it good. The cost includes 4 empty chips.

You will need an EEPROM burner to burn the chips until I make a programmer board, but to my knowledge this SIMM should be completely compatible with it when I have it ready.

Also to my knowledge this SIMM should work in any II series Mac with a 64-pin SIMM socket and the SE/30.

[olePigeon]

PM sent!

[Bunsen]

Would you also sell unassembled boards? I could use the practice

Ethernet / might get kind of confusing to set up because it would probably have to talk on IP

I was wondering about that too - but would it have to? As long as the board and the programming host can ID each other by MAC, all they'd have to exchange is raw ethernet packets, no?

a USB mass storage device that you drag the .bin file to, that way no drivers or extra software would be necessary at all (as long as your OS supports reading/writing FAT32).

Except the ROMs themselves aren't FAT, are they? How would that work then - drop the file to FAT storage on the programmer board, then the micro shifts it into the ROMs? Sounds convenient to the user, but inconvenient to you, and more complex and expensive for the board. The micro would have to read FAT, for starters.

(Though isn't that how some of those NXP boards work?)

But that may be too complicated in which case I would make an app that would talk to it as a USB serial device

Definitely sounds the simplest. Shirley there must be free/open source software around that could be used, adapted, or adapted to?

and use it as a generic EPROMmer, no?

That's a good argument for sticking with the sockets on my SIMM boards!

Well, it's 4 unnecessary parts (and points of failure) for most users - but the pads are still there on the layout, correct? So if anyone wants the socketed version, they can be simply be added?

Hope this is appropriate for quoting / I'm trying to differentiate between my response to Dennis Nedry and my response to you.

Entirely appropriate, for just that reason Or indeed any time when the last "concept" discussed in the previous post is not what you're responding to.

Basically, if reading straight through wouldn't make sense as a flow of conversation, and a word or two in your own post isn't enough to clarify

[dougg3]

Right -- the chips aren't FAT, so I would have to simulate the FAT filesystem. Whenever a file was written to the board, it would take the contents of it and write it directly to the chips. It may be kind of crazy to do, but I know the mbed LPC1768 board does that -- although it uses a custom chip to get it done. I like the USB-serial idea too, but the FAT idea is also intriguing. We'll see...

Yes, I will definitely make it a build-to-order option for whether someone wants a socket or not.

As for unassembled boards, sure! Do you want a kit with all the parts you need, or just the bare board? I would be happy to sell the bare board for $5 plus shipping, or a kit including sockets, capacitors, LEDs, a resistor, and 4 blank EEPROMs for $16 plus shipping.

If you want your own parts, you need four surface mount PLCC32 sockets, four 1206 0.1uF capacitors (5V or higher, I used 10V), and two 0805 LEDs and an 0805 resistor, with appropriate values considering a 5V source and the specs of the LEDs. I used two LEDs that have a 1.8V forward voltage drop each (Digi-Key part number 160-1421-1-ND), expecting 20 mA of current, and a 75 ohm 1/8 watt resistor, which will match with those voltage drops to give the LEDs about 19 mA of current.

[Trash80toHP_Mini]

Yup! if any thread needs to be kept in context, it's this 17 Page Development MONSTER!

[olePigeon]

Shouldn't this thread be stickied?

[Bunsen]

Well, I'd like dougg3's opinion on that, but I'd say not - this being the whole process of development from go to woah here. Perhaps dougg3, you'd prefer to make a separate thread to announce sales of the final version, when you feel ready?

[Trash80toHP_Mini]

I've hardly ever failed to see this thread in the active topics window, it doesn't even NEED to be stickied!

B's been stickyin' generally useful info, I'd say this is more of a hacks-n-development project thread, not a general use info thread . . .
. . . awesome as it is!

[olePigeon]

Now prepare for sheer awesomeness!

http://www.youtube.com/watch?v=nIpWPiBS2zg

It's my SIMM with custom boot chime and icons! Stay for the end of the video for the coolest Missing System icon ever!

Thanks dougg3! Coolest thing ever! Arrrrrr!

[PowerPup]

lol! "Arrr!" Sounds like the Mac is upset for being woke up.

Awesome graphics olePigeon!

Great work dougg3, you should get a "Macbel" prize or something!

[dougg3]

Thanks guys! Definitely cool artwork/sounds olePigeon

I agree that this thread probably doesn't need to be sticky'd, it stays active on its own

I was wondering at what point a new thread is appropriate. It is becoming a bit of a mess to follow everything! I'm planning on having a programmer board ready in the future, I'm thinking I will do a trading post thread once I have that ready (although I'm tempted to do it now...)

The title of this thread isn't very descriptive of what's going on in it entirely my fault! Haha

[Trash80toHP_Mini]

< mod mode >

The title is VERY descriptive of the first chapter!
How about a directory edited into the first page linking to the rest of the chapters?

off the top of my head:
__IIci ROM Hacking adventure
__ASC tomfoolery
__Reverse engineering the 68k ROM SIMM
__Rev0 ROM SIMM Development
__Trials and tribulations of Rev0 ROM SIMM DeGubbing process
__Rev1 ROM SIMM . . .
__ditto 2 lines above . . .
__Programmer Board R&D
__etc.

"Figure" index (per Apple's DevNote Model) with links to any posts with those (really annoying to myself ) FLASH dependent VideoClips of the ROM Hacks.

Whatchathink?

< /mod mode >

Keep it in a single thread format, with bookmarks on p.1 to entice people into reading through the entire saga, IMHO.

[olePigeon]

I object! There must be an entire chapter devoted to the Jolly Roger.

[Trash80toHP_Mini]

NoPro, put the list of links together to each and every post . . .
. . . IIRC "link to this page" or "copy link location of any given post" will do the trick . . .
. . . post them and yours will be the first linked "chapter" to be posted! (whenever I get around to it editing them into p.1)

[dougg3]

I like it! Good idea!

[Trash80toHP_Mini]

Cool, I may need to have the Chapters Linked to their respective sub-links pposted in a Second Thread that'll look like a post index of your 17 . . . and counting . . . page . . . Introductory Post. The links in that thread will . . .
. . . whatever, I'll figure it out as I go!

Any suggestions on how to streamline/improve this kind of project would be GREATLY appreciated!

This thread has just GOT to be some kind of freakin' record!

[dougg3]

This might need some reorganization/insertion/deletion/renaming but here is what I have after a quick skim of the entire thread (WOW! this thread really has come a long way from my original post about desoldering the DIPs and customizing the blinking question mark floppy disk icons!):

• First post (DIP ROM sockets, custom floppy disk blinking question mark icons)
• ASC tomfoolery
  
  • Custom synthesized startup sound (first few notes of Mario tune) and beginning of sampled startup chime adventure
  • Sampled startup chime (newer Mac startup sounds)
• ROM SIMM preliminary discussions and brainstorming
  
  • Reverse-engineering Apple ROM SIMMs
  • trag's SIMM design
  • tt's IIsi ROM SIMM X-ray image
  • Initial order of ROM SIMM rev. 1
• olePigeon's Jolly Roger logo
  
  • Integrating the Jolly Roger into the SIMM PCB rev. 2
• Arrival, assembly, and troubleshooting of the rev. 1 SIMM PCBs
  
  • Super long Mario startup chime to test expanded ROM capacity
• Brainstorming for programmability without the need for a chip burner and designing rev. 2 with that in mind
• tt's SE/30 with Power Mac startup chime
• Summary of changes in rev. 2 and later, additional changes
  
  • Final SIMM rev. 2 ordered
  • SIMM rev. 2 arrival, the fight with assembling it, and eventually success
• IIci troubleshooting and power supply testing
• Back to programmer board R&D (and other expansion brainstorming)
• olePigeon's customized ROM

[Bunsen]

Looks fine to me. If you like, I'll add it to the top of the thread.

[dougg3]

I would be thrilled if you would do that!

Back to the programmer board, I've started playing around with making a schematic for it. Looks like I can get away with using the AT90USB646 and one MCP23S17 I/O expander. That still leaves me with pins available for serial communication and a couple extra free pins, I'm thinking for status LEDs or something. I ordered some breadboardable DIP samples from Microchip of the MCP23S17 so I can see if it fits my needs.

Unfortunately, EAGLE light edition can't make a board big enough for the SIMM socket to fit (and the license doesn't let me make things I sell anyway--it's only for personal hobbyist projects). So I will have to switch back to FreePCB or KiCad or another alternative to create the board. For a project like this, laying out the board without a schematic (like I did with the SIMM) would be a nightmare so just doing the whole thing in FreePCB is not an option.

[bigmessowires]

You can remove the non-commercial restriction from Eagle Light by purchasing a $49 license. It still has the same board size restriction, though: http://www.cadsoftusa.com/shop/pricing/?language=en

There's also a $125 Eagle Hobbyist version, which has double the board size limit, but it's restricted to non-commercial use.

Beyond that, Eagle gets expensive pretty quickly if you're paying for it from your own pocket.

Among cheap/free Eagle alternatives, KiCad seems to have by far the most community support. I get comments on my blog every few days from people telling me what a dope I am for not using KiCad.

[dougg3]

Oh thanks! I didn't see the $49 license when I was looking at their pricing. I think I can purchase the $49 license and rotate the SIMM socket 30 degrees or so. That way it fits on the board. It looks kind of funny, but it will work! That makes me happy because I've taken all this time to learn how to use EAGLE, and I'd rather not have to learn another one

[Bunsen]

I've added a link to your index to the top post, dougg3. I'll add the index itself when I'm on a computer. It was too big for my phone's copy buffer, lol

[Trash80toHP_Mini]

Done deal!

[dougg3]

Thanks Bunsen & jt! Looks great!

[Bunsen]

Do you want a kit

I'm not properly set up workshop-wise just yet, nor do I have an EPROMmer. So I'm kinda waiting to see how the prog board works out