#Power chime mac how to
#Power chime mac series

So based on how the LC III did it, I wrote a program to test playing a sound by talking directly to the sound chip on my IIci. You determine whether there’s room in the chip or not by reading a status register. To write sampled sounds to the Apple Sound Chip, you basically just keep writing samples, one at a time, as long as there is room in the chip. Its sound chip is not quite the same as the IIci’s, but the way it plays its sampled sounds at boot time gave me a few clues. The LC III is one of the oldest Macs that has a sampled startup chime. To begin, I disassembled an LC III ROM dump.

#Power chime mac series

I decided to inject one of the sampled startup sounds from the LC/Performa series into my IIci:Īnd here is the sampled startup sound from the 5200/5300/6200/6300 series Macs: Here’s are some videos, followed by how I did it and how you can do it. Without any of the aforementioned people, I would never have been able to get this far in my hacking!

#Power chime mac how to

I’d like to share how I did it, as well as provide instructions on how to patch your own IIci’s startup sound with the sound of your choosing.īefore I start, I’d like to thank the people in the 68k Mac Liberation Army forums for the help and encouragement, and also the people who coded the MESS emulator for leaving a very handy register reference for the Apple Sound Chip in their source code. I didn’t feel very optimistic about getting that done, but after a ton of reading, experimentation, and frustration, I have figured it out, and my IIci now plays a sampled startup sound when it boots up. At the very end of it, I talked about how it would be awesome to figure out how to play a sampled sound at boot time, which would allow me to play any sound I wanted, limited by space available in the ROM. I shared a video showing how I customized it to play the first few notes from the Super Mario Bros song. I talked about how I replaced the ROM chips on the motherboard with sockets and disassembled the ROM code. I must admit I have not tested it yet.In my last post, I wrote about how I had figured out how the Macintosh IIci’s synthesized startup sound works. I’m really glad it’s back, I just hope they have restored, as a default, the diagnostic association with POST too. A relatively quick and easy fix all due to the Mac’s chime system associated with POST. The tones were in a specific order that pointed to the RAM DIMMs. What gave me the rapid diagnostic tool to point out what was wrong? The start up chime.

For example, while maintaining a large number of Macs back in the late 80s and early 90s, I had a bunch of RAM DIMMs that were failing across several machines. If you knew the meaning of the order of the tones you could rapidly diagnose the problem.

If POST did not pass the different tones did not sound together but rather sounded individually in a specific order. The startup chime, once it moved to a combined multi-tone way back when, actually gave you diagnostic information if the POST (Power On Self Test) did not pass all tests. There’s literally no technical reason it needs to be there, and it only serves one purpose - to delight the user… Which is exactly why it’s a big deal.” “Bringing back the boot chime isn’t functional. MacDailyNews Take: Our Macs are whole again, now Terminal commands required! While we rarely reboot anymore, certainly compared to the the pre-Mac OS X days, when we do, we like our Mac’s to chime on startup! There’s literally no technical reason it needs to be there, and it only serves one purpose - to delight the user… Which is exactly why it’s a big deal. If you think the startup chime serves one specific purpose, when that purpose no longer exists, you have no need for the chime…īringing back the boot chime isn’t functional. That’s important, and it’s also easy to overlook when you think of it purely from a functional standpoint. Most likely, removing the startup chime was a signal that the Mac is like the iPhone or iPad in that they’re essentially always on… the thing about the startup chime is that it’s a part of the identity of a Mac. At the time, Apple didn’t say anything about why it was removing the sound you hear when you start up a Mac. When you heard it, you knew your Mac was going to boot up. Over the years, the chime changed several times, but the purpose was the same: to tell a user that the computer’s hardware had passed diagnostic tests and was working properly. The startup chime had been around since the original Macintosh, though at the time it was more of a beep. It might seem like a small change, but it’s actually a big deal. This year, happily, Apple reinstated the Mac’s chime by default. Ah, the beauty of having Unix under the hood. Those of us who missed the Mac’s chime brought it back with a simple command in the Terminal.