A3k will not boot after battery change, do I need to run SetBatt?

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abraXXious

abraXXious

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OKiez, I changed out the battery for a lithium one, but now when I boot the HD light comes on and stays on and nothing else happens.

If I hold both mouse buttons or remove the hd I can make it to the kickstart screen.

I have read this is common when battery power is removed from the a3k for any length of time, but I have 3 a3ks and this is the first time it has happened (perhaps I was just luck the other times?).

Anywho, is this normal? Do I just put setbatt on a floppy, boot with no start up and run it?

Help! :)
 
Either Setbat or SCSIprefs will work. When you disconnect the battery the SCSI configuration is reset to default.

Usually, it's because the default mode is asynchronous and you were previously using synchronous. You may be able to disable synchronous mode on your hard by changing a jumper. I did this on my Compaq 550 MB SCSI2 and it works in both modes!

But it could also be because the SCSI controller address default is 7 and you have also have a SCSI device set to address 7. I don't why anyone would need to change the default but it's possible.
 
Thanks mate.

Used Setbatt, and changed the timeout to a higher value, also set synchronous and a couple of other things - all working great again.

@ Buzzfuzz - yessum, I put in the diode so the system cannot attempt to charge the non chargible lithium cell. I know what you mean about the a3k. I have 3, and the other two I have done the battery hack to, both worked fine with the default settings. This is the first a3k to need setbatt to boot. Weird.
 
abraXXious said:
Thanks mate.

Used Setbatt, and changed the timeout to a higher value, also set synchronous and a couple of other things - all working great again.

@ Buzzfuzz - yessum, I put in the diode so the system cannot attempt to charge the non chargible lithium cell. I know what you mean about the a3k. I have 3, and the other two I have done the battery hack to, both worked fine with the default settings. This is the first a3k to need setbatt to boot. Weird.
Click to expand...

I didn't expect the SCSI timeout to be an issue unless you have a very old (pile of junk) SCSI hard drive or you have motor start delay enabled. Do you enjoy slow booting your A3000?

@buzzfuzz
The problem with the "Diode" coin battery hack is that you have a .6-.7 volt loss across the diode. You will have battery failure when the voltage drops to approx. 2 Volts as seen by the clock chip.

Most Lithium batteries can tolerate a trickle charge but the trickle charge for a 1 ma Lithium is much lower than for a 60 ma Ni-Cad. So I would increase the resistor values to limit the trickle charge to a safe value if I were doing the coin battery hack.
 
Last edited:
Well, its an IBM 2gb scsi hd, but it seems to require it..... unless it was simply the lun setting, might experiment a bit....
 
@SpeedGeek: I'm using Schottky diodes on my units and the voltage loss is only 0.2V at full current (which the Amiga circuit never requires). :)

Typical voltage drop in the diode using the 1mA current the Amiga requires from the clock circuit when off is around 10mV and will not make such a voltage drop.
 
@rkauer
Thanks for the info.

@abraXXious
See rkauer's note about using a "Schottky" diode on your coin battery hack.

LUN should be disabled because there are very few SCSI devices which support it. Check the jumper settings on your IBM HD and make sure you have motor start enabled and motor start delay disabled. You need to get the drive to spin up ASAP after power up.

Note: Some drives have "brain dead" firmware and won't acknowledge an SDTR until after they are completely ready to transfer data.
 
In fact even an ordinary silicon diode will be good for the lithium because the very little current involved, but since Schottky diodes are affordable (price difference for just one unit is negligible) and have this very little voltage drop I prefer they. :nod:
 
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