68kMLA Classic Interface

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Centris 610 dark vertical lines
Posted by: theonetruetom on 2024-08-23 17:09:16 I've been fixing on my Centris as I want to get it to a good mechanical state before I bother Retrobriting. I've noticed that ever since the recap, I get this pattern at boot: Once it boots, it goes away: This thing is still kind of finicky about actually booting an OS sometimes, even though my prior thread in the adventures of this machine (where it wasn't chiming a lot of the time due to some bad solder around a component) has been basically resolved. I got a PiSCSI to mount internally so I can use my 25-pin BlueSCSI for other things, but this thing seems to have some issues booting from that device, often hanging at a floppy disk screen that doesn't flash when a viable image is selected by the PiSCSI, or the actual Pi service crashing in the middle of hard disk operations and corrupting my A/UX partition. It's never had a single problem booting off an external BlueSCSI. Anybody have an idea what I can look at/test to track down that screen issue? I don't think it's scanconverter related, since the issue goes away after the OS boots. My Mac display adapter is very old, but I don't remember it having graphical weirdness when I used it last. My gut tells me there's something not quite right still, but I don't know enough about where to look to diagnose it. I vaguely remember Adrian doing a basement video where he had a similar problem on one of his Macs, or maybe it was Action Retro, but I can't remember what Mac or how long ago. It seems like these issues could be related to each other in my opinion, but I don't have an oscilloscope currently and wanted to start with a good visual/microscope inspection of any problem areas. edit: less chonky pictures
Posted by: Byrd on 2024-08-23 17:14:45 Try another monitor - looks like a syncing issue with the LCD
Posted by: theonetruetom on 2024-08-23 17:40:06 Try another monitor - looks like a syncing issue with the LCD I hooked it up to the only other monitor I have with VGA that's close by, and that made the plot thicken even more: That TV may have a bad VGA port, or it might be having some trouble with the sync frequency, though.
Posted by: finkmac on 2024-08-23 18:21:17 sorry i don't see where the plot thickened? i just see two (rather garbage) LCDs that suck at scaling the 610's video output.
Posted by: theonetruetom on 2024-08-23 19:06:53 I mean, if you want to bring over a CRT, I can test with that, but this is being scaled by an OSSC, and it seems to happen at whatever resolution I set my adapter to and whatever monitor I connect up.
Posted by: Byrd on 2024-08-23 21:23:02 I used to have a Phillips TV like that - was great! Can you take away the OSSC, connect natively neither look like VRAM faults, rather LCD sync and then a not unusual moire pattern off the second display.
Posted by: theonetruetom on 2024-08-23 21:25:15 I used to have a Phillips TV like that - was great! Can you take away the OSSC, connect natively neither look like VRAM faults, rather LCD sync and then a not unusual moire pattern off the second display The second TV is straight VGA from the 15-pin adapter. I don't have a native monitor for this, unfortunately.
Posted by: theonetruetom on 2024-08-28 14:49:46 Update: I finished recapping and repairing a IIsi, figured out some weirdness with my display adapter, and the IIsi's display does the same thing on the OSSC. So yeah, probably just some scan converter weirdness. The issues with the PiSCSI on the Centris are a bit concerning, though. Does the 610 provide termination power on the internal bus?
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