Hello NeXT Community: I'm helping troubleshoot a NeXT 68040 25MHz Cube , the current drive is DOA.
I sent out one of my preconfigured SCSI2SD Cards version 5.1 with same set up I've used on hundreds of NeXT's . Verified it booted here on a NeXT Cube 68040 25MHz same ROM version before sending it as usual.
The Cube freezes up and throws checksum errors and does nothing trying bsd -s, we tried resetting the bios battery as well.
In the past Checksum usually had to do with problematic floppies or mismatched drives.
On PCs on boot it is usually a close to DOA bios battery , one of my guesses.
To eliminate the hardware I'm sending out another version 5.1 card with SD preconfigured a 2 connector new old stock SCSI cable and a new bios battery .... if it still spawns the same error
my best guess is new CAPS will probably resolve it.
Has anyone experienced checksum errors right off the bat when booting up a NeXT?
I looked here for further enlightenment on error codes
http://www.nextcomputers.org/NeXTfiles/Docs/NeXTStep/3.3/nsa/09_StartShut.htmld/index.html#9sbe any help appreciated.
http://www.asterontech.com/Asterontech/NeXT_POST_Codes.htmlThe checksum is one of the first steps and comes from a bad ROM. Causes could be:
1) Bad caps
2) Bad ROM
3) Bad CPU
Does the cube boot OK with no drive installed?
Hi,
Thank you both for your help, hope everyone is doing well given COVID-19. As good a time as any to look after some old hardware.
In any case, the ROM monitor given a b sd(0,0,0) command returns:
Bad cksum
Bad cksum
Bad cksum
Bad cksum
Bad label
and then a NeXT> PROM prompt. Going to try to find a suitable SCSI drive around here to hopefully prove out if it's a bus level problem. The SCSI2SD is accessible (read config, write XML config, etc.) and the SD card can be read/written to with checksum verified from a Mac.
Capacitors look fine at a glance (can't see underneath well without removing them, and at that point might as well replace them).
Thanks again + take care.
Ah, OK, different checksum.
1) Pull the battery to clear the PROM
2) Enable/disable parity in the ROM monitor
3) Sometimes the 68040 is picky about termination. There is a jumper on the SCSI2SD for onboard termination try it in both positions.
4) I blindly replace board capacitors at this point. Just assume they are bad.
Thanks -- The SCSI2SD 5.1 board does termination in software, disabling it resulted in SCSI Bus Hung error (not surprising), reenabling it seems to have fixed the problem. The XML configs generated before and after the change are identical, so it must be something internal to the SCSI2SD board. Fun stuff, seems to be working fine now and repeatably so.
Thanks again and take care ...