SCSI issues...

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Title: SCSI issues...
Post by: gtnicol on September 21, 2013, 11:09:43 PM
One of my turbo cube boards and a regular 25MHz board both exhibit the same behaviour: they say "selection failed" for a drive that other machines see fine (though the initial SCSI tests pass).

I'm wondering if this is likely the SCSI chip, or just the regular dry solder or perhaps failed caps?
Title: Re: SCSI issues...
Post by: Khashoggi on September 21, 2013, 11:57:00 PM
Quote from: "gtnicol"One of my turbo cube boards and a regular 25MHz board both exhibit the same behaviour: they say "selection failed" for a drive that other machines see fine (though the initial SCSI tests pass).

I'm wondering if this is likely the SCSI chip, or just the regular dry solder or perhaps failed caps?

I always go for the least complicated answer first: caps, solder, then silicon.
Title: SCSI issues...
Post by: barcher174 on September 22, 2013, 02:08:11 AM
I had this issue on an 040 board. It turned out to be bad caps.
Title: SCSI issues...
Post by: gtnicol on September 22, 2013, 09:55:35 AM
I'll look at the caps and solder... both boards will boot fine from an external drive, but get "selection failed" on the internal connector.
Title: SCSI issues...
Post by: Rob Blessin Black Hole on September 24, 2013, 01:39:28 AM
Quote from: "gtnicol"I'll look at the caps and solder... both boards will boot fine from an external drive, but get "selection failed" on the internal connector.

Have you tried it with an external scsi terminator ?  If it works then it is probably termination power or termination to the drive jumpers not in place.

Or Terminating resistors not in place on the drive.

If it doesn't work, check for a bent pin on the onboard connector or a cold solder or separated on board scsi connector / power connector from the board

I just uploaded a ton of troubleshooting scsi issues docs to http://www.blackholeinc.com/docs ... Chef is concating them so they will be easier to use. Appendix C shows all the original specs and jumper settings for the early monster cube drives!  

Best regards Rob Blessin

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