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That other opamp possibility didn't turn out to work, because it was too high a slew rate. Going to try another one, because supply of the original opamp is drying up and I don't have many of them.

Circling back to this project, I just tried the Samtec SMS-117-01-G-D as a possible new source for the connector on the backlit portable's screen cable. Sadly, the connector housing is *just barely* too large. The pin spacing is correct, but the socket doesn't want to fit. With a little...

PCBs are expected to be here on Thursday. I'm looking for two testers, DM me if interested.

Pictures of what? The F4 BlueSCSI products? Those are on my website.

I've tried this specific overclock configuration. It actually results in a decrease of read/write performance, for reasons I don't quite understand. Drops to 1700k read and 1500k write on beige G3. This overclock is a little weird and doesn't seem to realize that although [(25 * (500/25)) /...

This feature has been in the BlueSCSI codebase for a rather long time, actually. I think it was called out in this release because it had never been officially 'mentioned in a release notes' before. F4 BlueSCSI uses the same configuration as upstream, as mentioned in the Usage section of the...

Order is in for a small run of both PCBs: the new dual-opamp replacement and the style using original parts only.

Another pre-release set of binaries has been generated, to fix formatting-utility-related errors: Release Link: https://github.com/androda/F4_BlueSCSI/releases/tag/1.1-SNAPSHOT-2022-06-27 Firmware Update Steps: https://github.com/androda/F4_BlueSCSI/wiki/Flashing-Firmware-Updates

Digging around a bit, I found an dual opamp which hopefully can replace the original (and hard to find) opamps with one newer and cheaper chip. Going to pursue that as a possible update to the design before officially producing these. Less reliance on vintage parts is better. Haven't found...

Do we have any information about which panels are specifically affected by tunnel vision? I'm pretty sure there were 2 manufacturers for many of the grayscale displays in laptops. Do we know if it's only one brand that has the issue? The unfortunate thing is that being certain which display...

I'll try their specific configuration to see what it does.

It appears that the time has fully arrived: The A/D line is fixed, or close enough to the original that it behaves the same way. One resistor value wasn't quite right (basically the same thing I've said over and over again thus far). I can now run my Portable on battery power without it...

I attempted some overclocking this morning. The STM32F411 chip is rated at 100MHz. Overclocking to 125MHz resulted in a lockup on boot. Tweaking the F4 series' flash read accelerator didn't help. I had to change the AHB peripheral pre-divider to get the chip to start at this speed, and...

As shown in this Wikimedia image: https://upload.wikimedia.org/wikipedia/commons/7/76/Apple_Macintosh_II_motherboard.jpg It looks like things are implemented with: HAL16R8 HAL16L8 (under the nubus slots) These are the mask programmed (not flashable) versions of the more common GAL16 style...

I am unsure whether overclocking would increase transfer rates. BlueSCSI currently only speaks "Asynchronous SCSI", which is a slower protocol. "Synchronous SCSI" is faster, but much trickier to implement with current hardware. Overclocking is something I've been meaning to look into, out of...

When will which part be available? There's no overclocking support in the F4 series currently. Here's the F4 BlueSCSI discussion thread: https://tinkerdifferent.com/threads/f4-bluescsi-a-bluescsi-fork-by-androda.1336/

A new Release Candidate build has just been posted. If you are able to flash the update and do some testing, it would be very much appreciated. Release Candidate Link: https://github.com/androda/F4_BlueSCSI/releases/tag/1.1-SNAPSHOT-2022-06-21 Firmware update steps...

I think most people refer to 'vintage' as 'I had this when I was a kid and now I'm 30+'. In general I'm in favor of anything which is 'abandoned' needing a place to be discussed, and why not here? This sounds like a seriously cool system though, what a strange combination of design choices.

Pink spots are generally caused by being stored in a stack. The trackball presses against the LCD and pixels start to die. PowerBooks should be stored on their edge, with no compressive force, to avoid the trackball killing LCD pixels. edit: alternately, remove the trackball before storage...

Here you go: https://archive.org/details/Macintosh68kSchematics