Recent content by 8bitbubsy

Awesome! Will this speed-up make sense on a Macintosh SE as well? EDIT: "System 6 includes QuickerGraf (originally QuickerDraw), system software used to accelerate the drawing of color images on the Macintosh II." I guess not.

True, it works fine as is, but if there were to be some speed benefit using either the old or new driver, I'd stick to that one.

Thank you. :)

Should I use the disk driver supplied with System 6.0.7's Apple HD SC Setup on a stock Macintosh SE, or are there any benefits with using the one in Apple HD SC Setup 7.3.5? Also wondering if there are any non-Apple drivers out there that are faster, or otherwise better.

If there's a market for these things, but I kinda doubt it. You need to source a SWIM chip in the first place, and that's not going to be easy. Maybe it would be better to try and replicate the SWIM chip with a microcontroller instead (or an FPGA if needed, but that would be costly).

I see, but I still don't want to design this PCB after all, since I've never designed a PCB before and it's a lot of work. At least I have verified that the PLCC44 SWIM variant will work when rewired to DIP28, so that's something.

So yeah, using a PLCC44 SWIM from a Macintosh IIsi is confirmed to work on a Macintosh SE with FDHD ROMs. I initially thought all my work was wasted as I got garbage on boot, but it turned out the chip enable (/G) wire had broke off on the high ROM as you can see in the picture, so I had to...

Well, if you allocate a massive chunk (a few megs), then it could take a noticable amount of waiting time. I assume NewPtrClear is the same as calloc, right?

Nice investigation! :) One could have a clear length threshold, f.ex. 128 bytes, where anything higher than that would enter a highly optimized 32-bit aligner+clearer, while anything shorter or equal would use the original low-overhead version. EDIT: movem.l d0-d7,-(An) comes to mind for...

I've been optimizing my mixer a little bit. Instead of checking for the sampling end points in the inner mixing loop, I run a calculation loop that determines how many samples I can mix before I reach the end of the sample (or sample loop), so that the inner mixing loop can be branchless (gets...

Awesome, enjoy the machine!

I have also blown this exact part, it connects to the eject mechanism. My guess is that something jammed the eject motor so that it used too much current (or that it was connected wrongly?). In my case, replacing it with the same part from a broken drive made it work perfectly fine again.

Thanks, this is awesome! Back when Symantec actually made good non-bloat software...

Has the board been recapped? Also look for bad traces, especially near the SWIM chip. Sometimes traces can be bad under components too, so I recommend testing traces near the capacitors with a multimeter. EDIT: Just checked, some traces from the SWIM chip actually go under the C8/C9 capacitors...