welp, how'd i get into THIS situation? let's rewind...
*earlier* what i have here is a Sun SPARCstation 1+.
it's going to need a little work but WHAT is that blob of duct tape
looks like a coin cell mod.
on the back, we have the usual semi-cursed 13W3 video connector and the Sun keyboard connector. where am i going to find a Sun keyboard?
i just happen to have one, new in box! i bought this years ago at Weird Stuff Warehouse when they were still around. i have no idea why, but i'm glad i did.
i've also got some Sun mice. an M3 and an M4.
however, they have RJ11 connectors and the keyboard (which is where the mouse plugs in) just has a mini-DIN connector. uh oh.
which brings me back to here. does this mouse, despite the connector difference, use the same protocol?
looks like it is essentially the same protocol as the version of the mouse (type 4?) designed for the SPARCstation. the output is open collector, inverted async serial, 5 byte.
time to build an adapter. the connector is RJ11 (technically 6P4C) but it has these pins sticking out, presumably so you can't plug it into a phone jack.
ahh well, i'll just file some grooves.
adapter!
couldn't find a Sun 13W3 cable adapter so I'm doing this to get to VGA.
well it found the keyboard!
four months later  i made the Video Snake Oil board that can adapt 13W3 (any type!) to VGA. you just wire up the little pads to whatever your machine needs.
i've also installed a ZuluSCSI. this neat little board is a lot cheaper than a SCSI2SD. i'm going to try and install Solaris using a CDROM ISO file. CD6_512.iso is placed on the SD card. it'll be ID 6, 512 bytes per sector.
well, it tries to boot from the CDROM but suffers a BAD TRAP. not sure why, maybe i need to update the IDPROM contents.
yeah i am guessing the machine type in the IDPROM is invalid so the installer runs the wrong code.
wrote a little FORTH program to update the contents of the IDPROM, and it looks like it has a valid host id now.
forgot to add that i needed to do a "set-defaults" and a "setenv diag-switch? false"
uh oh, RAM parity error. i'm hoping U676 isn't seated all the way and that it is an easy fix.
that did the trick. the SIMM sockets were very stuck. welcome to S O L A R I S!
spoke too soon. another parity error, this time at U677. why there? because that's where i moved the module that was at U676. think i will just pull that bank of RAM for now.

it seems to run with 12MB RAM. no more parity errors this time. but now the installer hates my SCSI drive (a ZuluSCSI).

filesystem creation failed for / 🤔

i bet it is this issue. basically the ZuluSCSI returns values for disk geometry that somehow confuses the Solaris partition tool. one solution is to use a real SCSI hard drive and then dd it over to the ZuluSCSI once the install is completed.

https://github.com/ZuluSCSI/ZuluSCSI-firmware/discussions/122#discussioncomment-4418076

Has anyone used ZuluSCSI on a SPARCStation? · ZuluSCSI/ZuluSCSI-firmware · Discussion #122

Hiya, I've got my ZuluSCSI installed in a sparcstation 2 and while it's definitely working...something is amiss. I can boot from CD image and Solaris 2.7 sees the hard drive image but I've having s...

GitHub

zululog.txt has the smoking gun:

[996859ms] WARNING: Host used command 0x1A which is affected by drive geometry. Current settings are 63 sectors x 255 heads = 16065 but image size of 2097152 sectors is not divisible. This can cause error messages in diagnostics tools.

i think the solution here is to resize the disk image file so it is divisible by 63*255*512.

that wasn't the solution lol  there's no more zululog.txt error but the superblock isn't getting written correctly. 6D B6 DB 6D is the test pattern written by the format command. could be somehow corrupting it during the write?
@tubetime 6D B6 DB is a worst-case test pattern for MFM encoding, so the NAND flash chips in your SD card must not have enough timing margin for the channel code.