A1200 boot problems!

[melange]

Hi I'm just wondering if you are aware of the fact that you should never plug anything into your Amiga while it's on.  This includes Monitors, Joystick, Mice, Printer or Serial cables and external floppy disk drives.  In fact anything.  With amiga's you should always powerdown and add that cable/device, then powerup again.
With today's PC's you can plug most things into them with out it being a problem.  Example Monitors, Parallel printers, serial cables, etc... while the computer is rinning.  You just can't do that with Amiga's.  

Hopefully you have not been doing that and your problem is the floppy drive.  My personal experience with floppy drives is that most problems come from dirty drives and or disks.  Remove the drive and give it a good clean.  Isopropyl alchol (Video Cassette Head Cleaner) with a cotton tip will do the trick.  Very gently manually clean the drive heads.  If you have any high quality electrical lubricant (Contact Cleaner) put a tiny amount into the rear of the step motor(Do not get it on the heads).  The heads run on a rail, which can also benefit from a clean and lube.
If all goes well the drive will work again and be a little more quiet, when accessing the disk.

I this fails, then the drive may well have had it's day.  Talk to Amikit for a replacement, or mod a PC drive.  However, modding a PC drive can be a longwinded process.

Good luck

BTW the result of plugging things live into the Amiga is quite often a blown (8520) CIA chip.  This unfortunately is a surface mounted chip in the A1200, and would require someone with a high level of soldering skills and the appropriate equipment to remove and replace it.  As well, you would have to locate someone selling them, or massacre another Amiga  :boohoo:

[melange]

I once blew a CIA in my A500, because I forgot to turn it off when I plugged in the Mouse.  The mouse 9 pin plug had  metal surrounding the 9 pin plug and it shorted the pins together on the mouse port as I awkwardly tried to insert it.  I, just like yourself, have been swapping joysticks and mice live for years, but not if it's got metal surrounding the plug.  So yes you are correct, but IF I recall, it was always recommended to get an auto Joy/Mouse swapper, rather than doing it manually.  The auto swappers make a clean safe swap.

However...

On a quick inspection of the A500 schematics, the Joystick/Mouse ports have little or nothing to do with the CIA's.  However, the floppy drive has plenty goin on in the CIA department.
The joystick port signals, all go to a 74 series chip and after that are associated with the Denise chip.  Perhaps I don't recall that particular saga as clearly as I thought.  I do remember seeing a spark on a port as I plugged a lead in.  May not have been a mouse at all
 :crazy:

[melange]

Cool, maybe I'm only half insane then!   :crazy:  :crazy:  :lol:

[melange]

As long as I can remember it has always been seen as a golden rule.  Even though some games did require you to change from mouse to joystick, it was always scorned upon.  All the help articles I read in magazines, were constantly reinforcing the power down before you plug-in rule.

[melange]

With the exception of PS2 Mice and Keyboards, actually, you can plug and unplug from a live PC.
If your PC is an AT or XT, then maybe not, but for the current crop of modern PC's, you can plug in printers to the Printer port, SVGA Monitors to the Video Card, sound cables to the sound card, any USB device of Course, serial cables, firewire, cables for video devices, etc...  It's all handled just fine.  I teach InfoTech at a TAFE college here in Australia.  We have a large screen and projector in my classroom, that they have never bothered to purchase a switch for, in order for me to switch from the PC's Monitor to the large screen/projector.  I must have swapped from large screen to PC monitor over a thousand times now, and done it while the PC is powered on everytime   :-D
No problems.

Further more I have watched classrooms full of students plugging peripheral devices one after the other, into powered up PC's.  The MANUALS don't even tell you to power off anymore, half the time.

I have fried an Amiga 500 plugging things into it live, but never a PC.

So sorry, but based on a ton of experience and what is quite clearly become considered acceptable practice, I beg to differ.

[melange]

@Tomas

Agreed!  I think what needs to be considered here is that,  if you really stuff it up while inserting a device into a port on your PC and you blow something, you go to shop and buy another for peanuts.  The same thing does not apply to the dwindling quantity of Amigas, Amiga hardware and replacement parts that remain.

Folks, if we are all not a little more careful we will have even less machines to play with in the future.  An awful lot of these machines will die from age.  We don't need to help them along.  Power down your Ami before you plug stuff in.

I often wonder how many younger newcomers, who have become interested in the Amiga, after learning to use a PC, have inadvertently killed the Amiga, by plugging things in while it's live.

[melange]

Hey, am I seeing that correctly?  Shouldn't the yellow (assuming that's shield, Amarelo=yellow?) wire be connected to the ground for shield.  Isn't it kinda dangerous to have +5v around the shield?  :-?

[melange]

Yep, I agree, we have strayed off the subject a little.  I am very concerned about that PSU Mod above though.  The A500 manual shows the Sheild connected to ground.  God knows what would happen if you did that.  Assuming the mod above worked, I'm kinda suprised.
@rkauer
Have you done this mod?

[melange]

It's got like a POWER SHIELD!!!  :lol:
Extra, extra protection from..........  something?   :oops:

But seriously, I hope nobody uses that to mod with an 1200/500 PSU lead, it's wrong, and if it was to touch ground...  :shocked:  :-o  :-(

As lokki has pointed out.  The shield does not have to be connected at all, but it most definitely should not be connected to +5V