Re: New to this hardware

On Feb 17, 2026, at 4:29=E2=80=AFPM, McGrude <[email protected]> wrote:
>=20
> For disk(s) I intended to us a ZuluSCSI sd card scsi emulator I have =
one hand.
> For PSU I am going to use an ATX power supply with a break out board
> to get easy access to +5, +12, -12 to power the backplane.

First, get the docs for the boards you have, they're on Bitsavers. =
Having Motorola BUG ROMs is good because they're pretty comprehensive in =
their support for booting from a variety of media. According to the docs =
on Bitsavers it does look like the 162 will support your 712M transition =
module.

Having the correct documentation for your board and configuring your =
board properly with the various DIP switches and jumpers is *critical*. =
You may not damage anything otherwise, but you may also not be able to =
do much of anything with that board either. (I have a pile of i860 =
boards that I hope to someday find docs for=E2=80=A6)

Second, ensure your ATX supply can actually provide enough power on =
*all* of the rails. As the world moved away from 5V TTL to 3.3V to 1.8V =
etc., power supplies moved away with it. I have some Meanwell supplies =
to specifically meet the V/A requirements for my VME gear.

Third, you're probably going to have an easier time with the MVME177 =
than the 162 when it comes to NetBSD; the 1x7 boards are more =
general-purpose while the 1x2 boards are more self-contained embeddable =
controllers. I'm not sure what NetBSD's 1x2 support is like, the 177 is =
definitely supported though as I've run NetBSD on mine.

Finally, don't worry too much about SCSI (at least at first) since you =
have other NetBSD and Linux systems and experience netbooting UNIX =
systems. Netbooting something like the MVME177 is actually quite =
convenient: Paging over Ethernet isn't really any slower than paging to =
a supported SCSI disk, and you can also have the console serial port =
connected to aa host so you can even do things like drop to 177Bug by =
sending a BREAK signal, which will let you remote-reboot in case of a =
panic/hang/etc.

What I've generally done with mine is set up the board according to the =
manual in something close to its default configuration, boot to 177Bug =
and use the configuration commands to set the NVRAM configuration to its =
defaults, and then use 177Bug to netboot NetBSD. =46rom there it's =
"just" NetBSD.

  -- Chris

PS - I'd start with either NetBSD 11 since RC1 just came out, or NetBSD =
CURRENT, because there have been lots of 68K improvements in both. The =
improvements in CURRENT are more extensive (and therefore riskier) but =
sometimes that's part of the fun!=