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| I present to you an EVT TNT Power Macintosh 7500 Prototype Board and More | |
| Posted by: jajan547 on 2022-09-19 22:03:29 To begin I would like to first say I'm ecstatic to have this board and I plan on putting it in a 7500 case (sadly I have no case or ROMs for this board) and hopefully tracking down or with the help of someone here creating a new ROM SIMM. This is pretty unique in that it is an EVT which don't typically show up in the wild. This board has a date of 1994 TNT BOARD REVISION 820-0564-05, EVT-3. This board also came with an external video connector board I assume this to also be a prototype as it's markings say "AV HOISDEN" with a part number of 820-0609-01 dated 1994. I have added photos below and will elaborate further....   The board as we can see has a somewhat odd layout compared to final units, things clear to me such as apparent reset and interrupt switches, missing or different connectors, no on board ROMs.   I know you see the weird chip with wires more on that further down.... As we can see no on board ROMs are present   Apparent Reset and Interrupt Switches      Serial Number is *FC506VJNEVT*  EGRET appears to be a 341S0060    Better view of more chips on Board   Now for the chip you all are probably very interested in it appears Apple had issues with this chip and decided to try hijacking it or piggybacking a chip. As can be seen many bodge wires done by an Apple Engineer are attached to a 44 pin PLCC socket which connect to an AMD MACH210A-10JC. I assume there's a great interest on reading this chip and what's on it I currently don't think I have a programmer (all I have is a TL866ii Plus) that can read this chips contents (correct me if I am wrong). I would love to extract whatever information is this little chip but I want to go about it the right way, if you're interested in helping PM me 🙂. Now onto the little Video Board "AV Hoisden" (820-0609-01)    Things I still need are a donor 7500, a ROM SIMM, a Recap, and to of course move the ticking time bomb that is a Maxell Battery. I hope you guys enjoyed this. If you have any questions, ideas, feedback, or anything please feel free to PM me or comment below. Im interested in learning more about this. | |
| Posted by: slomacuser on 2022-09-19 23:02:29 Great 🙂 looks like a fun project for you. I can ship you RAM, video RAM, ROM and some PCI cards to try 😉 | |
Posted by: jajan547 on 2022-09-19 23:05:59Great 🙂 looks like a fun project for you. I can ship you RAM, video RAM, ROM and some PCI cards to try 😉Will those ROMs short anything or cause damage? | |
| Posted by: slomacuser on 2022-09-19 23:11:01 I have mixed ROM and CACHE on 6100 without damage so you can try ... | |
Posted by: jajan547 on 2022-09-19 23:19:43I have mixed ROM and CACHE on 6100 without damage so you can try ...I'm all for it, worth a shot. | |
| Posted by: joshc on 2022-09-20 02:00:18 I think I'm right in saying this, as I vaguely recall a fairly lengthy thread about it... Be careful about how you wire up a PSU for that board, as 7x00 series boards seemed to have different pinouts and there was a lot of confusion as to which pinouts belong to which 7x00 board. @mg.man Does that ring a bell? | |
Posted by: mg.man on 2022-09-20 02:46:53@mg.man Does that ring a bell?Very much so... real confusion btwn the 7300 / 7600 - in my experience, not interchangeable despite some inferences you can... 😕 I don't know about the 7500 though. As @joshc says.... be careful! | |
Posted by: mg.man on 2022-09-20 02:48:39I vaguely recall a fairly lengthy thread about it...I believe you're referring to this one -- 7500 Power Supply WoesI have a 7500 machine that was robbed of it's power supply by the previous owner and a few other parts. In trying to track down a powersupply cheaply for it I came across a 7200 for sale on marketplace it was a pretty good deal $80 including shipping so I figured that's perfect I will get my...
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| Posted by: joshc on 2022-09-20 03:02:16 That's the one! | |
| Posted by: macuserman on 2022-09-20 03:21:57 Haha that’s my thread! I think I probably have enough spare parts for these darn machines to make a whole new one including the chassis/case. I was on quite a quest there for awhile. Where the blazes are you located @jajan547 ? | |
Posted by: Phipli on 2022-09-20 03:37:05I have mixed ROM and CACHE on 6100 without damage so you can try ...How do you mean? I'm not certain but think you are talking about how you can switch the ROM and cache on Nubus PPCs? Or switching ROMs between similar macs? The ROM and cache slots are different sizes on a 7500 os you can't mix them up. Like I mentioned in the thread, the 7500 uses an identical ROM to the 7200, 8500 and 9500 so a simm version of those could be used no problem. | |
Posted by: slomacuser on 2022-09-20 03:42:23How do you mean? I'm not certain but think you are talking about how you can switch the ROM and cache on Nubus PPCs? Or switching ROMs between similar macs?   | |
Posted by: Phipli on 2022-09-20 03:44:04View attachment 46654Yesss.... thank you, but that isn't a 7500. | |
Posted by: jajan547 on 2022-09-20 04:08:07Haha that’s my thread! I think I probably have enough spare parts for these darn machines to make a whole new one including the chassis/case. I was on quite a quest there for awhile. Where the blazes are you located @jajan547 ?I’m located in the USA, North Carolina specifically. Still there is the problem of finding the simm as you can imagine I don’t want to solder ROMS to an EVT board, can I yes but I want to track down one. | |
Posted by: al kossow on 2022-09-20 07:18:39To begin I would like to first say I'm ecstatic to have this board and I plan on putting it in a 7500 case (sadly I have no case or ROMs for this board) and hopefully tracking down or with the help of someone here creating a new ROM SIMM. This is pretty unique in that it is an EVT which don't typically show up in the wild. This board has a date of 1994 TNT BOARD REVISION 820-0564-05, EVT-3. This board also came with an external video connector board I assume this to also be a prototype as it's markings say "AV HOISDEN" with a part number of 820-0609-01 dated 1994. I have added photos below and will elaborate further....I would love to extract whatever information is this little chip. It is a workaround for a bug in the Hammerhead memory controller. | |
Posted by: jajan547 on 2022-09-20 07:19:34I would love to extract whatever information is this little chip.Did you work on developing this computer? What was the bug? | |
| Posted by: jajan547 on 2022-09-21 00:28:48 Is it possible to extract the Information off that chip? | |
| Posted by: Bolle on 2022-09-21 00:52:49 Yes, with an appropriate programmer and if the chip doesn’t have the security bit set. Not sure if they’d secure it because it supposedly never should have never made it to the public. So worth a try to read it out. | |
Posted by: jajan547 on 2022-09-21 05:02:41Yes, with an appropriate programmer and if the chip doesn’t have the security bit set. Not sure if they’d secure it because it supposedly never should have never made it to the public. So worth a try to read it out.I’d love to know what’s on it I’m sure it’s some pretty interesting if not valuable information I wonder if anyone has a programmer nearish to me. | |
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