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SE/30 battery bombed repair attempt
Posted by: LeSpameur on 2025-04-09 07:34:11 I ordered a Din-8 to Serial cable, to see if I can get an error code.
Posted by: Callan on 2025-04-09 08:08:28 Since you had battery damage I would check continuity of all your data / address lines. . Start with your rom socket to cpu. Seen a number of issues there. After that I would check everything going from rom socket to the mux'. There is a pin to pin matrix that someone was nice enough to make at the end of the schematics. That will make it easy for you quickly verify what pins to test.
Posted by: LeSpameur on 2025-04-09 09:24:35 Since you had battery damage I would check continuity of all your data / address lines. . Start with your rom socket to cpu. Seen a number of issues there. After that I would check everything going from rom socket to the mux'. There is a pin to pin matrix that someone was nice enough to make at the end of the schematics. That will make it easy for you quickly verify what pins to test. I checked all the vias underneath the battery — they're all good. But I'm not entirely sure the new F258s are installed the right way, since there were no markings on them.
Posted by: croissantking on 2025-04-09 10:30:32 I checked all the vias underneath the battery — they're all good. But I'm not entirely sure the new F258s are installed the right way, since there were no markings on them. Got a photo? They’re usually tapered on one side - the side that has pin one.
Posted by: LeSpameur on 2025-04-09 11:52:06 Got a photo? They’re usually tapered on one side - the side that has pin one. There’s no marking or anything on the chips, even under the microscope.
Posted by: LeSpameur on 2025-04-09 11:53:20 There’s no marking or anything on the chips, even under the microscope. I used F258AD, not F258. They’re from Philips.
Posted by: croissantking on 2025-04-09 13:11:56 There’s no marking or anything on the chips, even under the microscope. All of the chips have a bevel on one edge, including the ones that have lost their markings.
Posted by: LeSpameur on 2025-04-09 23:45:36 All of the chips have a bevel on one edge, including the ones that have lost their markings. I swear, there’s nothing on the new F258AD from Philips ! I looked under the microscope !
Posted by: MacUp72 on 2025-04-10 00:05:26 do you have a photo before the repairs/ ultrasonic cleanings? it helps locating spots for clues
Posted by: croissantking on 2025-04-10 00:16:13 I swear, there’s nothing on the new F258AD from Philips ! I looked under the microscope !
Posted by: LeSpameur on 2025-04-10 04:47:53 View attachment 85357 View attachment 85358 Okay !!! Sorry, I feel a bit stupid right now. But at least they're correctly in place. The Mini-din 8 to serial cable is coming home...
Posted by: LeSpameur on 2025-04-10 04:50:30 do you have a photo before the repairs/ ultrasonic cleanings? it helps locating spots for clues Unfortunately, no. The ultrasonic baths didn't change a lot. This morning I checked almost every traces around the battery, the copro and the muxes, they're all fine ! Even the vias !
Posted by: LeSpameur on 2025-04-10 23:45:42 Unfortunately, no. The ultrasonic baths didn't change a lot. This morning I checked almost every traces around the battery, the copro and the muxes, they're all fine ! Even the vias ! Found that I tried to use the “hidden test mode”, but I cannot type anything on the terminal. I was using Tera Term with the good settings (9600 baud, 8 bits, 2 bits stop, no flux). Same thing on a working machine in crash state, so my mini din-8 to serial cable might be bad. Apparently some cables are not connected. I ordered an other one, hopefully it works.
Posted by: djc6 on 2025-04-11 04:33:24 Apparently some cables are not connected. I ordered an other one, hopefully it works. It needs to be wired as a null modem - DB9 null modem adapters are available. This is pinout of my working TechStep cable - I originally made it as a cable for ADTPro software for Apple IIgs:
Posted by: GreenBar0n on 2025-04-11 12:07:00 Found that I tried to use the “hidden test mode”, but I cannot type anything on the terminal. I was using Tera Term with the good settings (9600 baud, 8 bits, 2 bits stop, no flux). Same thing on a working machine in crash state, so my mini din-8 to serial cable might be bad. Apparently some cables are not connected. I ordered an other one, hopefully it works. I'm having a difficult time with the Test Mode too. Was able to get the Transmit Line Feed, and Local echo setup in the Terminal tab of Tera Term, it looks like it behaves and works correctly now when pressing A and 5, but I get no answer from an SE or SE/30, using my newer PC and Prolific USB/COM port adapter. I also never get the Sad Mac screen/tone while connected via TeraTerm, or when pressing the Reset or NMI either. I even tried older drivers for my Prolific adapter, 5.1.3.0:
Posted by: djc6 on 2025-04-11 12:59:54 I also never get the Sad Mac screen/tone while connected via TeraTerm, or when pressing the Reset or NMI either. What about on your working Mac SE? Do you get Sad Mac tone when pressing Reset button? Mine on my SE/30 did nothing when I pressed it, until I spray DeoxIT into the programmer's switch (aka reset aka NMI)
Posted by: GreenBar0n on 2025-04-11 13:51:51 I'll try both SE's, but no Sad Mac when connecting the COM cable, and pressing either of the two buttons on the side, which on all three boards does Reset when pushed.
Posted by: LeSpameur on 2025-04-12 01:22:48 It needs to be wired as a null modem - DB9 null modem adapters are available. This is pinout of my working TechStep cable - I originally made it as a cable for ADTPro software for Apple IIgs: View attachment 85420 Thanks! I bought that one :
Posted by: croissantking on 2025-04-12 05:01:37 You can also just connect up to another Mac with a regular DIN-8 to DIN-8 serial cable.
Posted by: LeSpameur on 2025-04-12 05:11:21 You can also just connect up to another Mac with a regular DIN-8 to DIN-8 serial cable. Really ? I'll be able to communicate with it ? I thought it wasn't possible. Which software should I use ?
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