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Imac keyboard Power button - won't work to boot, but will in OS X??? Help?

R

ran

macrumors newbie
Original poster
Jan 13, 2004
11
0
Hi everyone!

Well, here's the story:

Scrounged: Imac 350mhz slot-loader (indigo)
Scrounged: Imac keyboard

This thing was missing some bits and pieces (e.g. HD, mem, PRAM battery, some case parts, etc...)

I scrounged all that up, put it together, and found that pushing the power button on the Imac itself seems to work just fine. Unfortunately, I'm missing the "inner button" part of the power button, so, when the case plastics are put together, I can not use that power button.

So, I thought, aha! I'd just use the power button on the keyboard.

Well, I find that pushing that button will *not* power up the computer. However, if I start the computer with the power button on the computer itself (have to pull off bottom case plastics), then I find that OS X is responsive to the keyboard's power button by prompting for, 'Shutdown, Sleep, or Restart'.

So, that means the button works, right?? Well, if so, then why not to start up the computer???
(everything else on the keyboard seems fine)

I've tried removing/reinstalling the PRAM batter, resetting the PMU (by pushing that little buttonpad on the logic board for 30seconds)..but all to no avail.

*WHY* would the keyboard's power button *only* work after the computer is started but not to start it up??? :confused:

Ran
 
R

reaper

macrumors 6502
Apr 9, 2004
267
0
19th Hole
I don't believe thata OS X supports that functionality. It uses the "power" button for the sleep and shotdown dialog once the computer is on, but I don't believe it will turn on the computer as it would have in OS 9 or earlier.

- reaper
 
R

ran

macrumors newbie
Original poster
Jan 13, 2004
11
0
Hi reaper and thanks for the reply...

What I meant by that was that there was no physical problem with the button - the computer can recognize when the button is depressed..so why can't the computer recognize it when it is off?

As an addendum, I've also tried the following:

Put in a new PRAM battery (checked voltage, reads ~3.54)

Reset NVRAM by doing the following in Open Firmware:
reset-nvram
set-defaults
reset-all
(the last ended with an automatic chime/reboot)

This still hasn't solved the problem. I know others have seen it, as reference on this webpage...but so far haven't found a solution..

anyone else? :cool:
 
R

ran

macrumors newbie
Original poster
Jan 13, 2004
11
0
oh..wait a minute...are you saying that power on by keyboard just isn't supported if the boot system is OS X? In other words, if I switch it back to OS 9...it should work?
 
R

ran

macrumors newbie
Original poster
Jan 13, 2004
11
0
OK, I just confirmed at work that an IMac running OS X 10.2.x will powerup just fine from a keyboard power button..so that's not it... :cool:

Any other ideas?

Could the firmware be "partially corrupted" or something like that?

Ran
 
whooleytoo

whooleytoo

macrumors 604
Aug 2, 2002
6,607
716
Cork, Ireland.
ran said:
OK, I just confirmed at work that an IMac running OS X 10.2.x will powerup just fine from a keyboard power button..so that's not it... :cool:

Any other ideas?

Could the firmware be "partially corrupted" or something like that?

Ran
Click to expand...

I believe Apple are removing this functionality (the Power button is already removed from new Apple keyboards) due to an issue where powered USB devices could cause your Mac to spontaneously boot up.

I don't know how precisely it's being disabled (i.e. is it the OS, or firmware that's changed to disable the power button).
 
O

osprey76

macrumors 6502
May 3, 2004
300
0
Oklahoma City, OK
whooleytoo said:
I believe Apple are removing this functionality (the Power button is already removed from new Apple keyboards) due to an issue where powered USB devices could cause your Mac to spontaneously boot up.

I don't know how precisely it's being disabled (i.e. is it the OS, or firmware that's changed to disable the power button).
Click to expand...

That makes sense to me. I know changing USB configurations will often wake the computer if in deep sleep.

I've also read that Apple removed the power button because if the keyboard was connected through a hub the power button would not always make the computer boot. So, are you running the keyboard through hub at all?

My mom has a Sawtooth G4 running 10.3 and as far as I remember the power key was working fine last time I was home. My memory is a bit hazy since that was some months ago.
 
Hemingray

Hemingray

macrumors 68030
Jan 9, 2002
2,926
37
Ha ha haaa!
The iMac keyboard's power button should definitely boot the iMac, I would think that functionality should be independent from the system. Is the keyboard the same one that came with the Indigo? If it's a different one, it's possible that maybe it's somehow not compatible with the computer. (Recently I tried plugging a Rev.B iMac's keyboard into a Rev.A iMac and it went totally wacky. Not sure if it was a compatibility problem or a bad keyboard, but the keyboard was working fine not six months prior.) That's all I can think of...
 
O

osprey76

macrumors 6502
May 3, 2004
300
0
Oklahoma City, OK
Hemingray said:
The iMac keyboard's power button should definitely boot the iMac, I would think that functionality should be independent from the system. Is the keyboard the same one that came with the Indigo? If it's a different one, it's possible that maybe it's somehow not compatible with the computer. (Recently I tried plugging a Rev.B iMac's keyboard into a Rev.A iMac and it went totally wacky. Not sure if it was a compatibility problem or a bad keyboard, but the keyboard was working fine not six months prior.) That's all I can think of...
Click to expand...

As I think about it, I agree more and more with you. Even if Apple has discontinued the power key and the ability of the computer to boot from a USB trigger, I don't see how they could turn this off in older computers. Firmware doesn't load until after the computer is booting up. The system software has no bearing on the most basic level of turning on the power. Though, it's interesting how the splash screen soon after power on is OS 9 (gray) or OS 10 (white) dependent.
 
R

ran

macrumors newbie
Original poster
Jan 13, 2004
11
0
Thanks for the replies, everyone...

1. The keyboard is definitely *not* the one that came with the computer. Everything is scrounged/second-hand.

2. The keyboard is directly plugged into the side of the IMac.

3. Ummmmmm....well, that's where I am.

A question: Is it possible for the firmware to be partially "corrupt"?

That is, would reinstalling the 4.1.9 firmware possibly fix this? If so, how does one *RE*-install the firmware? Doesn't the updater check the current firmware and refuse to install if it's the same?

Thoughts?


---
Note: A kind person is sending me the inner power button for the Imac..so I'll be able to use that...but I *would* like to solve this issue.... :cool:

Ran
 
R

ran

macrumors newbie
Original poster
Jan 13, 2004
11
0
OK,

an update:

I've tested the keyboard at two macs at work, a G4 tower and an Imac..the keyboard works *FINE* powering up those two computers...so, it is definitely an issue with the Imac.

What do people think about the "firmware" issue mentioned above....could this be a culprit?

Is there a way to force the firmware to "reinstall"?

Ran
 
Finiksa

Finiksa

macrumors 6502a
Feb 23, 2003
595
13
Australia
ran said:
What do people think about the "firmware" issue mentioned above....could this be a culprit?
Click to expand...
I doubt it's the result of corrupt firmware. I have a G3 iMac and a spare keyboard with power button. If I recall correctly mine doesn't turn on via the keyboard, I'll connect it up later today and try again.

Did your iMac come with the Pro keyboard or button style keyboard when originally sold by Apple? Perhaps Apple just disabled support for this in newer models that didn't ship with the older keyboard.

I'm not really sure I haven't given it much thought before, but I think this is normal behavior.
 
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