SupraDrive autobooting

[sjprohaska]

I recently got a hold of a 20MB SCSI SupraDrive and interface.  I installed everything and it works fine, however I am unable to autoboot to the harddrive.  I can boot using the SupraBoot disc, but I cannot automatically boot to the drive when I power the computer (A500).  I have KS 1.3 on my system.  The SupraDrive manual states something about removing an autoboot rom from the drive but has no pictures of any kind and even refers to an additional manual which I don't have. I did remove the largest chip on the board with the same results.  Also, I have read another post that talks about jumpers and dip switches.  This SCSI controller contains neither.  Does anyone have any experience with this?

Thanks

[sjprohaska]

Thanks, but after closer inspection and re-reading the addendum, it appears my SupraDrive SCSI interface was made in early 1989.  Interfaces after 1989 have jumpers.  So I either have to add or remove an autoboot rom.  Out of 16 chips on the board, three are removable.  One is a large AMD chip and the two smaller ones read PAL16L8ANC.  I guess this model cannot autoboot.  It looks like it's all about floppy booting for me.

[sjprohaska]

Thanks.  Per your advice, I did a search on Ebay and picked up a AMAB6 chip for $10.  Can't wait to install it.

[sjprohaska]

The chip came but it does not seem to work and it is half the size of the previous chip.  I have a regular SupraDrive, not a SupraDrive XP.  Is there a big difference?

[sjprohaska]

It's just a regular SupraDrive that works with both the Amiga 500 and 1000, according to the manual.  I'm using it with an A500 plugged into the side expansion port.  The old chip is an AMD chip and it is longer (more pins) than the replacement chip.  If I remove the AMD chips it does not detect the drive.  If I place the new chip in, the same thing happens.

[sjprohaska]

It looks very similar, however there is no extra chip next to the scsi chip.  There looks to be solder leads that have a similar number of dots as pins on the new chip.  There is no other places on the board for
"insertible" chips.  I guess this board never had autoboot capabilities.  The manual and software that came with the card and drive seem to be newer.  I guess this is an older board.