Amiga 3000 Locks on any SCSI on boot.

matt3k

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I have a A3000T that give a solid yellow light and locks the system when you turn it on.
With no drive on the bus it boots from floppy just fine.

This started when I removed the accerlator (was still using the scsi bus with the accerator.)

Here is what I have tried:
* Tried different SCSI, ramsey, and dmac chips
* Tried removing terminator resistors on mb.
* Tried many different drives.
* Tried adding mutiple drives to chain.
* Removed battery to lose NVRam settings.
* Turned off all options in nvram.
* Tried removing all the fast memory.
 
Last edited:
Difficult advice.
You try install a clean system on a clean scsi disk, boot from install floppy and the run HDToolBox - dont use old system from previvous accelerator - so if you will boot up.

Do you use 030 on board or you have A3000T-040? I have similar problems with DMAC, RAMSEY, specially when I am using 3640 or CSMKII060. Help me combination 02,04 or 04,07. Some Ramsey have different timing, they work in A4000 but in A3000DT may not work correctly - laboratory.
Try external termination, from Commodore (3070) or active version from GGlabs (to modern scsi accesories). Check jumpers, check memory type (for burst), read A3000T manual 2.56-2.60.
I hope you make it happen soon.
 
The 030 is on the motherboard and works fine, ran system tests for memory and processor by booting from floppy.

I tried 2 different Ramsey 07 and dmac 04 combinations with the same results. I can try 04 and 02 combinations and see.

I will also try external termination.

My 3000T manual must be different, I don't have pages 2.56-2.60?

Jumpers on the 3000T seem to be right, I have tried a few different combinations.

I tried old scsi drives and a acard sup2000 sata2scsi, same results...
 
Bad cable, bad termination, incompatible or bad drives.

I've also seen Kickstart versions cause this. On one of my A3000's, 2.04 works fine with most drives, 3.1 will lock up like yours with some drives and not others.

It's possible to blow a diode on the desktop A3000 board that will cause issues with termination on external drives, but not sure on A3000T. I haven't had to repair enough of those to see that problem.
 
Hello,

Assahi tells important things! Then look if your motherboard has battery leackage, near FPU or near ROM sockets, or something related to memory (i suppose, now you have to use ZIP ram, right?).

Regards
Stefano
 
Hey Matt,

The SCSI LED staying on does sound like an issue between the 33C93A and your SCSI BUS. But if it turns out not to be something simple, you may want to try reseating/subbing BUSTER and GARY too, just to rule those out. I doubt either suddenly failed, but a flakey PLCC socket connection is certainly possible. BUSTER has some bus arbitration logic influnced by/influencing DMAC, and GARY is of course in the mix too.

Good luck!
 
Have you been able to solve your issue? I just had the same thing happen to me with an external SCSI device. Turns out the SCSI cable needed to go on backwards. With the SCSI bus locked up the HD LED was always-on. Flipped the cable and it works fine.
 
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