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Reverse Engineering the Macintosh SE PCB & Custom Chips for 1:1 reproduction


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No luck with SRecord....

max@dThinkPad:~$ srec_cat /home/max/Downloads/324s0440-b.bin -byte-swap 2 -o bs1.bin
srec_cat: /home/max/Downloads/324s0440-b.bin: 1: warning: ignoring garbage lines
srec_cat: /home/max/Downloads/324s0440-b.bin: 54: file contains no data

It just occurred to me though, the files is 1k, microchip only list the 16f54 as having 0.75k of memory?

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I think it's more likely that the configuration word needs to be set up properly, as this is not part of the main firmware and is hardcoded in the mask ROM versions of these chips.

 

Three settings are controlled by the configuration word: code protect, watchdog timer, and oscillator type.

 

The desired settings would be

Code protect (/CP): disabled (1)

Watchdog timer enable (WDTE): disabled (0)

Oscillator Selection bits (FOSC1:FOSC0): I can't tell you — the easiest way to determine the correct setting would be to measure the frequency on the OSC1 pin of a working SE board and then setting it appropriately. It would not be RC, as I don't see an RC oscillator on those pins, but it could be any of LP (00), XT (01), or HS (10). XT and HS should act identical when OSC2 is unused (as here), but LP will act differently as it's meant for a much slower clock, and RC will not work at all. My guess is that it's supposed to be HS or XT.

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On 6/7/2021 at 5:11 PM, max1zzz said:

It just occurred to me though, the files is 1k, microchip only list the 16f54 as having 0.75k of memory?


In the form of 512 12-bit code words packed as 512 2-byte words, which is why the first four bits of each word of the .bin file are always 0.

Edited by balrog
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1 hour ago, balrog said:

I think it's more likely that the configuration word needs to be set up properly, as this is not part of the main firmware and is hardcoded in the mask ROM versions of these chips.

 

Three settings are controlled by the configuration word: code protect, watchdog timer, and oscillator type.

 

The desired settings would be

Code protect (/CP): disabled (1)

Watchdog timer enable (WDTE): disabled (0)

Oscillator Selection bits (FOSC1:FOSC0): I can't tell you — the easiest way to determine the correct setting would be to measure the frequency on the OSC1 pin of a working SE board and then setting it appropriately. It would not be RC, as I don't see an RC oscillator on those pins, but it could be any of LP (00), XT (01), or HS (10). XT and HS should act identical when OSC2 is unused (as here), but LP will act differently as it's meant for a much slower clock, and RC will not work at all. My guess is that it's supposed to be HS or XT.

 I'll measure the clock tomorrow, as A quick test I tried what I think should have been the correct settings for HS and XT mode neither of which worked (I say think as the binary and hex representations of the config word shown in the minipro software don't seem to tally with each other. it seems that they are inverted but I need to look at it tomorrow when it's not nearly 3AM....)

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1 hour ago, Kai Robinson said:

Well, it looks like the repro boards have already hit ebay

 

And yet this is the same inertial who rail viciously against any other makers of scsi2sds, even the ones derived from the open sourced designs, even the licensed manufacturers and yell at their own customers when they dare to suggest that the sun does not shine out of their arsehole eternally and forever.

 

I don't know if they're ignorant of how hypocritical they are or just don't care; either way, I wish they'd piss off back to Amiga-land where this kind of behaviour is for some reason more or less expected.

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I'm changing the Github to clarify that this is under a CC-BY-NC-SA license which specifically prohibits commercial use.

I've already had one outfit (amiga of rochester) DM me about reselling these. I didn't respond. Inertial didn't even bother doing that. I'm fine with people taking this project and building off it, or making their own, but when i've yet to recoup my initial investments, and i'm still sitting on a stack of 20+ boards to sell, it's more than a little insulting.

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Unfortunately, he's the kid peeing in the pool.  The reason other people can't have nice things.

 

Hope he's proud of himself.  A profound ethical failure as a human being.

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11 minutes ago, Kai Robinson said:

Inertial didn't even bother doing that.

 

Welp, guess I won't be buying any of their products ever again. I imagine many others here will follow suit upon finding out about this.

 

It's a shame that people are so ravenous for a profit that they see fit to steal other people's hard work.

 

 

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@inertialcomputing do you have anything to say in regards to this matter?

I understand that there's a large swathe of people wanting these boards and i have zero issue with people downloading the publicly available files from this thread and making their own, but thats just it - i haven't released the files on GitHub yet for wider release, and when i do, it's under the NON COMMERCIAL license - if you want to resell, you can TALK to me first and maybe negotiate something. 

The reason for not releasing these on GitHub just yet is twofold

 

1) Recoup investment costs by selling a batch of boards myself - i have spent well over £1500 on this project.

2) in cases like @max1zzz discovered, I want to be the single point of failure/contact for issues. The latest board rev has a minor issue with extra pins needing to be connected to ground for the Serial to function correctly and not crash with System 7. 

I don't think i'm being unreasonable with this - If i sell you a board and there's something wrong - i don't just want to swap it out for another one, i want to help diagnose WHY the problem occurred in the first place, rectify so that ALL future boards can be fixed down the line with a new revision. Already i have v1.5b in production at the board house for testing (small batch of 5 this time). I may well take a loss (£200+ on ALL the latest blue boards) to save everyone in future from having to use a bodge wire or two for the grounds. Or i could just say that if you were considering purchasing a board and dont mind a bodge wire, you can have it for FREE, just cover shipping. Remember - unlike @inertialcomputing i supply a brand new 15.6672MHz oscillator with every board, and with the option of NEW SIMM sockets and new RTC / SND chips as a bundle in. 

I did not make this project for people to make a quick buck at my expense. I did this for the community as a whole.

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1 hour ago, cheesestraws said:

 

And yet this is the same inertial who rail viciously against any other makers of scsi2sds, even the ones derived from the open sourced designs, even the licensed manufacturers and yell at their own customers when they dare to suggest that the sun does not shine out of their arsehole eternally and forever.

 

I don't know if they're ignorant of how hypocritical they are or just don't care; either way, I wish they'd piss off back to Amiga-land where this kind of behaviour is for some reason more or less expected.

We have no problem with SCSI2SD V4-derived open source SCSI2SD's, as long as the derivatives honor the license. I'm not sure where you're getting your misinformation. We've done nothing wrong in attempting to get non-compliant manufacturers of SCSI2SD to open their derived designs, as required by the terms of the GPL.

 

1 hour ago, Kai Robinson said:

I did not make this project for people to make a quick buck at my expense. I did this for the community as a whole.

I reached out to you via a PM here _and_ opened an issue via GitHub back on April 29th: https://github.com/kr239/Macintosh-SE-Reloaded/issues/2

 

@Kai Robinson, you didn't respond to either attempt at communication, which is unfortunate. If you had, we simply wouldn't be having a discussion in an open forum, with you already annoyed. I'm happy to donate 100% of the profits of all sales of this board directly to you (a whopping five so far), or any charity you choose, less the actual manufacturing and shipping costs. I think what you've done is fantastic. I'm also more than happy to remove the item from sale entirely. Please contact me privately

Edited by inertialcomputing
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10 minutes ago, inertialcomputing said:

I'm not sure where you're getting your misinformation

 

You're lecturing me about misinformation.  That's bloody rich that is.  Note, please, that I said 'rail against', rather than registering legal complaints about; snide comments about how nobody's but yours are any good, spreading FUD about competitors.  You're great at never quite legally committing yourself, but still behaving very badly, and then having the absolute hubris to complain about other people speaking of you the precise way that you speak of other people.

 

Still, I'm not sure I should expect any better from a mediocre hack capitalist profiting off other people's expertise.

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4 minutes ago, cheesestraws said:

Still, I'm not sure I should expect any better from a mediocre hack capitalist profiting off other people's expertise.

 

With respect, I own a small business. I employ one person, part time, to fulfill orders. I also have a day job. I'm not getting rich here. I don't understand your need to portray us as some sort of predatory boogey-man. That's not who we are.

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2 minutes ago, inertialcomputing said:

I don't understand your need to portray us as some sort of predatory boogey-man. That's not who we are.

 

You could always try not acting like one.

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I see ONE request on github for a license, which i responded to today. Also, there's no link in my head to an "aperezbios" on github to an inertialcomputing whatsoever. Likewise, you didn't send a PM to me on the forum as inertialcomputing, but under another name entirely (included for reference).

Again, my not replying to your query was not tacit approval to plaster a fresh batch of boards all over eBay. If you ask, and dont get an answer, most people would assume the answer is: NO.

In both cases you wanted clarification on the licensing - well, it's CC-BY-NC-SA and will be in perpetuity as far as i'm concerned. 

The reason for not replying in both cases btw is just an oversight - not a deliberate snub. The only request i've received so far that i've not answered, is from another supplier wanting to sell the boards, something which i'm not interested in. It's very easy to get burned out from projects like this and TBH i needed to take a few days off. 

The whole reason i only posted the files here and not github, is so that the people involved can take the files and either have their own boards made, or make suggestions for bugfixes etc. Not once did i say 'YOU CAN SELL THESE COMMERCIALLY'. The only reason *I* am selling them at the moment is already explained above. Furthermore - to sell these commercially, among the wider community may incur the wrath of Apple themselves and then we may ALL lose. I sell these for little more than it costs to make and i STILL throw in extras to make it easier on people.

I have a day job. These boards are not my bread and butter. I just want to do fun things that have a net positive result for the community at large. I don't mind spending money on my hobby, but consider this: board runs for prototyping got expensive in the last year. Not so much the boards, but the shipping has gone astronomical. Last batch cost me closer to £300 once shipping and customs fees were taken into consideration. Am I being unreasonable for wanting to cover at least SOME of my outlay before i get undercut and outsold by others?

I'm not interested in the profit you've made so far, or a donation - I would just ask that this project to be removed from sale.

Right now, I'm starting to feel like a dehydrated man crossing the desert on the way to the sea, but the vultures are already circling overhead.

I *might* change the licensing in the future but for now, it stays as a NON-COMMERCIAL license with ONE important caveat:

*IF* you want to do a board run locally for yourself and you want to sell off the extras on the trading post - that's fine, that's not an issue. That, to me, seems fair.

On the subject of charity, however, if anyone wanted to donate money to a charity and not just myself or the other vital contributors - send some here: https://www.westonhospicecare.org.uk/ or here: https://www.shelter.org.uk/ - both organisations need it, moreso than ever. 

Screenshot 2021-06-09 at 4.54.20 pm.png

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1 hour ago, Kai Robinson said:

I'm changing the Github to clarify that this is under a CC-BY-NC-SA license which specifically prohibits commercial use.

 

@Kai Robinson Thanks. We're happy to abide by any stated license, and have pulled the listing. I've also donated £120 (USD $177) to Shelter UK, one of the two charities you cited above. ShelterUKDonation.PNG.f470ba8dd8034c3924eed8df485a1522.PNGShelterUKDonation.PNG.f470ba8dd8034c3924eed8df485a1522.PNGShelterUKDonation.PNG.f470ba8dd8034c3924eed8df485a1522.PNG

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Thank you - i consider this matter dealt with, so please, if everyone could return to their regularly scheduled programming, that'd be fine - i'm already having an aneurysm at work at the moment, i also don't need a 4th Heart attack! :(

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Just now, olePigeon said:

A 10MHz 68000 (MC68000P10) should work in one of the SE boards, correct?  It'll just down clock match the crystal or whatever is doing the timing?

 Yep - it will only run as fast as the system clock input. The clock speed on the case is just the speed it's rated for at max, officially. 

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