Announcing ZuluSCSI Pico (Open Source Hardware)

[rabbitholecomputing]

Today, Rabbit Hole Computing has released a version of ZuluSCSI, derived from our full-size ZuluSCSI RP2040 board design, under an Open Source Hardware License, the CERN OHL-S.

The KiCad 7 design files, as well as pre-prepared Gerber files, are available for download at https://github.com/ZuluSCSI/ZuluSCSI-Pico-OSHW.

A complimentary pull request that enables DaynaPORT SCSI Etnernet emulation (over Wi-Fi) is pending merging in to the ZuluSCSI code base, at https://github.com/ZuluSCSI/ZuluSCSI-firmware/pull/318. The DaynaPORT SCSI Ethernet functionality was originally contributed to the BlueSCSI V2 project (itself a fork of the RP2040-specific portions of ZuluSCSI), by the open-source contributor Josh Stein

 

[paws]

This looks fantastic!

Can I ask a general question about your platform, how tied up is the RP2040? Are both ARM cores in use?

 

[macuserman]

Nice job! I was waiting for this to come out!

 

[rabbitholecomputing]

This looks fantastic!

Thanks!

Can I ask a general question about your platform, how tied up is the RP2040? Are both ARM cores in use?

The RP2040 resources are in heavy use. In addition to having two Cortex-M0+ microcontroller cores, there are multiple PIO blocks (Programmable I/O), as well as state machines, all of which the ZuluSCSI firmware uses to accomplish its job. The microcontroller itself has 264 KB of static RAM, in six independent banks (four 64 KB, two 4 KB), and this finite resource is being pushed to the limit, particularly when the DaynaPORT/Wi-Fi code is in use, as it's necessary to buffer Ethernet frames in RAM, in order to achieve acceptable levels throughput (Around 120kB/sec)

The ZuluSCSI firmware itself is available for anyone to view, modify, and contribute to at http://github.com/ZuluSCSI/ZuluSCSI-firmware and is released under the General Public License/GPL, version 3.

 

[sfiera]

Are there plans to sell this board with the SMD components pre-soldered?

 

[Phipli]

Are there plans to sell this board with the SMD components pre-soldered?

You could just order them from JLCPCB with the SMD components presoldered.

 

[Forrest]

Very nice!

 

[rabbitholecomputing]

Are there plans to sell this board with the SMD components pre-soldered?

There are indeed plans, and we've already produced a batch of boards, which we took delivery of yesterday. While we're still working out the logistics of creating kits from these, if you are interested, please contact us directly, or just stay tuned here.

These are _not_ JLCPCB-produced or assembled boards. ZuluSCSI OSHW Pico Boards assembled and sold by us and/or our distributors will include Rabbit Hole Computing branding/logos, so it's possible to tell the difference between boards produced by community members, or other commercial use.

 

[MrFahrenheit]

This is awesome. Thanks for everything you do for this community!

 

[twelvetone12]

This is great news, very cool!

 

[tt]

Great looking design. I'm guessing the RP2040 will eventually get an upgrade so it may useful to have that part of the design remain modular.

Does the wifi work ok inside a case with shielding?

 

[zigzagjoe]

Thanks for releasing this! I've already modified it to meet my own particular goal: the smallest external SCSI device out there.

Initiator mode is no longer possible and termination is fixed enabled (unless you remove the resistors responsible, anyways) - but otherwise functionality and firmware compatibility should be the same as the original. Cost is probably more expensive as a 4 layer board is required along with a specific DB25 connector & surface mount headers for the pico w.

Boards on order, we'll see how it works out. Source at https://github.com/ZigZagJoe/SillyTinySCSI

 

[eharmon]

Thanks for releasing this! I've already modified it to meet my own particular goal: the smallest external SCSI device out there.

Initiator mode is no longer possible and termination is fixed enabled (unless you remove the resistors responsible, anyways) - but otherwise functionality and firmware compatibility should be the same as the original. Cost is probably more expensive as a 4 layer board is required along with a specific DB25 connector & surface mount headers for the pico w.

Boards on order, we'll see how it works out. Source at https://github.com/ZigZagJoe/SillyTinySCSI

View attachment 64466

Wow, basically plugs right onto the back of any device. That could be really handy!

 

[3lectr1cPPC]

That tiny board looks pretty cool! I do worry a bit about clearance issues with that on some macs though. I remember that already being an issue on one of the SCSI devices, forget which one.

 

[zigzagjoe]

We'll see how it works out. Width-wise it's the narrowest out there, but it's definitely a smidge taller at 25mm total without case (the DB25 is centered in the middle of that). It looks like some of the quadras recess their SCSI ports though. The SCSI board has the port protrude by about 6mm, however there are some 3mm tall caps.

If the rear of the quadra's scsi port to the nearest protruding edge of the case is 3mm or less, it'd fit. I did come up with a more conventional first design that'd work for anything, but it's less small.

Here's a crap MSpaint dialog if what needs to be measured....



I'm hoping it works well, with the new wifi functionality added I'd think it'd be a super handy external only option. I ordered a few partially-populated boards so I may toss the extras up for sale.

 

[3lectr1cPPC]

At the very least, most people being able to use it would still be pretty nice. I 100% agree that these would make a great easy Wi-Fi dongle of sorts. Well, as easy as SCSI anything can be that is.

 

[Phipli]

That tiny board looks pretty cool! I do worry a bit about clearance issues with that on some macs though. I remember that already being an issue on one of the SCSI devices, forget which one.

You could always stack it with a male/female pass through "adapter" or two.

 

[joshc]

Thanks for releasing this! I've already modified it to meet my own particular goal: the smallest external SCSI device out there.

Initiator mode is no longer possible and termination is fixed enabled (unless you remove the resistors responsible, anyways) - but otherwise functionality and firmware compatibility should be the same as the original. Cost is probably more expensive as a 4 layer board is required along with a specific DB25 connector & surface mount headers for the pico w.

Boards on order, we'll see how it works out. Source at https://github.com/ZigZagJoe/SillyTinySCSI

View attachment 64466

This is the coolest thing since sliced bread. Please add me to your imaginary waiting list.

 

[zigzagjoe]

You could always stack it with a male/female pass through "adapter" or two.

Good point. I also forgot there's an alternative DB25 that should allow up to 14mm from the back of the scsi connector too. Anyone care to measure how much is needed?

 

[tt]

View attachment 64466

Wow, I wouldn't have thought this would be possible based on the original layout! It's nice to have the board more flush with the back of the computer case so it is less likely to get knocked into or bent. Looking forward to seeing more of this variant.