Macintosh SE ROM Replacement PCBs...

[AlexCL]

Kai Robinson had a post on another forum with a PCB for replacing Mac SE ROMs with common EPROMs. Do we know the resistor rating for the RN1?​

I attached the gerbers for that board from the post.

Macintosh SE EEPROM to ROM adapter

So, you have a Mac SE, or you're building up a Mac SE reloaded board using damaged donor that might have bad ROM chips (corroded legs, dead chip etc). Well through the magic of the internet I can bring you this, an adapter that replaces the stock Toshiba TC531000 mask ROMs with any 27C010's...

68kmla.org

 

[retr01]

Hello, @AlexCL.

If referring to the R1, the values are 10kΩ 1/4W 1%. I was not able to find RN1 on the SE logic board. Is it the R1 in the A1 area of the board?

If you meant another resistor, please let me know. AFAIK, the SE board has resistors starting with "R" and then a number.

 

[retr01]

By the way, much information, including values in the BOM (bill of materials), is generously provided in those videos. Let me know if you need help getting to the list directly.

 

[AlexCL]

Thank you for the resistor values...the resistor pack in the attached photo is the item I need to ID...an actual part number would be helpful if someone has that as I'm an electronics newb but can cross-reference.

I'm looking at the ROM board to create custom ROMs with ROM Disks for booting the system from ROM like the Classic.

Also playing with the PiStorm on the Mac SE and might want to use custom ROM code for (if I can figure it out) for stability/extended features.

I've been lurking on the scene and following the Mac SE Reloaded saga on and off.

I found that I ordered 20 of the PCBs from June of 2021 and wanted to dust them off and try to create some custom ROMS.

 

[AlexCL]

FDHD ROMS are some of the unavailable chips...so this board could be used for the Mac SE Reloaded builds too.

 

[Kai Robinson]

@max1zzz made better ones than me

 

[AlexCL]

@max1zzz made better ones than me

Thanks for the reply...do you remember the value of the resistor network at RN1 for the adapter board? Please let me know as this is the last item I need to order to make a board.

 

[Kai Robinson]

Iirc I calculated them as 1k

 

[AlexCL]

Thank you so much for the Reply...I bought a variety pack from Amazon and it has 1K resistors in the pack.

 

[dankcomputing]

Unfortunately this board doesn't fit next to a PLCC SWIM:

 

[JDW]

Unfortunately this board doesn't fit next to a PLCC SWIM:

Could be that the SWIM replacement solution by @Kay K.M.Mods won't fit either, but since there's no product dimensions given on his product page, it might be prudent to ask:

Super Wh-IWM Swapper, PLCC44 to DIP28 SWIM adapter | infinityproducts

This is a SWIM chip adapter that allows you to upgrade an early SE to a 1989 SE FDHD (1.4MB Super Drive) without using SWIM on the DIP28. The SWIM chip can be used with a spare PLCC44.There are more details on my blog. Logic boards from which parts can be stolen: , Mac SE/30, LCI/II, Quadra700...

www.infinityproducts.co.jp