akimmet wrote on 2024-06-20, 18:44:

So, if I understand correctly this project is essentially a SBC with a SCSI interface in target mode? So similar in idea to PiSCSI, except hopefully far faster than the RasberryPI gpio interface.

It would make sense to use FreeBSD, since it was one of the only open source operating systems that supported SCSI targets on a traditional SCSI bus.

It is good to hear you are doing better, and still able to work on this project. Life in general can always get in the way when you least expect it.

That is essentially what it is. But it has a real SCSI controller chip not a software emulated one!

This is what I was hoping for. Either a real SCSI controller, or perhaps a CPLD or FPGA to drive the SCSI bus.
Not a micro controller trying to emulate a controller over their gpio interface.

Oh yeah, it's much faster, I currently see write speeds of over 60MB/s and read speeds of around 40. Once I fix the TCQ issues I expect this to get closer to the theoretical maximum of ultra-2 speeds.

I just created an account to follow along with this. I have a AlphaServer DS20 that needs a reliable disk system, I'm down to one functioning 4.3 GB drive, and being DEC, it's a bit finicky about what devices work.

When more details come out, I'd love to give this a test.

CD audio is actually a very important feature to me. In terms of games and old systems - which this board is about - I'd say it's critical

Hey @TMM is this still in the works?

@TWM

Hi TWM

I might have a specific Use-case for this Emulator, possibly as a Business case too., depending on -Compatibility- within the targeted Environment.
Or as an alternative ... you could technically assist / develop an emulation for specific drive types.

Are you interested and can we get in contact electronically ?

Thank you
Ron

TMM wrote on 2024-06-21, 13:22:

Oh yeah, it's much faster, I currently see write speeds of over 60MB/s and read speeds of around 40. Once I fix the TCQ issues I expect this to get closer to the theoretical maximum of ultra-2 speeds.

Hi,

Any updates on this project? Last post was almost a year ago so I am guessing it may be dead but if it is not: In many ways it sounds like the Acard ARS-xxxx line. If you can get it working at a reasonable price point it would be fantastic. Someone had said $100 to $200 as a target price. I guess if you are a business and really need it great. However, as a hobbyist for $200 I would have to pass. I am hoping this could be a $20 to $50 adapter which can be mass produced and purchased in bulk (e.g. I would replace my 18 drive SCSI RAID with it). But you know what they say "If wishes were horses, beggars would ride". 😆

Aside from what you have listed my wish list would be:

1. 50 pin, 68pin, and 80pin versions
2. U160 or U320 speeds

Thanks and good luck!

This idea sounds nice in principle, but wouldn't it be cheaper just to buy those $20 NOS 300 GB U320 15K hard drives off of eBay? I bought some 2 years back.

feipoa wrote on 2025-03-12, 07:01:

This idea sounds nice in principle, but wouldn't it be cheaper just to buy those $20 NOS 300 GB U320 15K hard drives off of eBay? I bought some 2 years back.

Yes and no. Those 15K drives are great but they can be noisy and produce tons of heat, so not well suited for most older systems with poor airflow, and eventually you will need replacements. Also they can be wasteful on an older system (e.g. I have a 486 EISA system with wide 20mb/s 2.0GB HDD drives running MS-DOS 6.22 as the OS so a 2GB partition and 298GB unused). A solution like this pretty much future proofs us for our lifetime and likely the lifetime of the machines we are using them on. Plus as fast as the 15K drives are they are still slower then an SSD.

The ultimate (and probably super expensive) solution would be to build a 3.5" SSD HDD with a good/great smart SSD controller and a SCSI interface using large capacity chips. Given that most older systems/OSes are not smart enough to deal with SSD and optimizing read/writes having larger capacity chips that can be used to map out defects and replace dead/dying cells with a smart flash controller would be great for redundancy. These could be drop in replacements for current drives.

I think the main issue is the cost. If both options were at cost parity, everyone would go for the idea you propose. If your proposal ended up being, up to 3x the cost of an alternative, I would buy your product. Just that the two alternatives are only about $20 - the alternatives being NOS SCSI HDDs and ACARD+CF.

For the NOS U320 SCSI, to reduce heat, people can grab the 10K drives or use drives with lower capacity. The last I looked, which was 2-3 yrs ago, I saw some 36, 72, and 137GB NOS U320 10K drives. For my systems, I found adding an internal case fan blowing at the HDD sufficiently cooled the drive. I've mostly used these drives in mid-sized towers. For systems which are heavily overclocked and nearing the CPU's heat limit, I found the U320 15K drives added just enough heat to cause CPU instability. For that system, I went with ACARD+CF. The ACARD adaptors were only about $22 and need a firmware swap to get working with HDDs.

Could you add a photo of your prototype?

feipoa wrote on 2025-03-13, 05:00:

The ACARD adaptors were only about $22 and need a firmware swap to get working with HDDs.

Where do you get ACARD adapters for $22 ?
And which speed of SCSI do they support?

Disruptor wrote on 2025-03-13, 12:28:

feipoa wrote on 2025-03-13, 05:00:

The ACARD adaptors were only about $22 and need a firmware swap to get working with HDDs.

Where do you get ACARD adapters for $22 ?
And which speed of SCSI do they support?

aliexpress & ebay are the standard go to
Ultra-160 scsi ... was that the correct name? tired & needing to eat :-p

https://68kmla.org/bb/index.php?threads/conve … aec-7726.38935/ to convert the CD acard adapters to HDD .

I think that's what feipoa means.

feipoa wrote on 2025-03-13, 05:00:

I think the main issue is the cost. If both options were at cost parity, everyone would go for the idea you propose. If your proposal ended up being, up to 3x the cost of an alternative, I would buy your product. Just that the two alternatives are only about $20 - the alternatives being NOS SCSI HDDs and ACARD+CF.

Like I said it probably would be expensive. The flash memory and controllers should be cheap enough. A quick look on Amazon shows you can get a 250GB SSD from brand names for $21 to $50 (that is for a Samsung). I think the real cost is going to be either in the SCSI controller chips (which are probably hard to find in quantity) or the programmable ASIC that would sit in between. When I spoke to the SCSISD guys they told me the reason for not having a wide version basically came down to development costs and the cost of parts.

Honestly, the real make it or break it point is ~$100 for a drop in solution i.e. 3.5 inch form factor devices with 256GB of flash memory and a SCSI interface. Anything above that and it isn't worth it in the hobbyist market because as you pointed out you can just buy a $20 U320 drive and get a 68 pin to 50pin adapter for a few bucks more.

As far as the ACARD last I looked at it the "real" adapters (e.g ARS-2320) are super expensive and the $20 ones you are referring to are hit and miss and require desoldering FLASH ROMs and reprogramming. Certainly not a do it yourself project for everyone...

weedeewee wrote on 2025-03-13, 16:11:

aliexpress & ebay are the standard go to Ultra-160 scsi ... was that the correct name? tired & needing to eat :-p […]
Show full quote

aliexpress & ebay are the standard go to
Ultra-160 scsi ... was that the correct name? tired & needing to eat :-p

https://68kmla.org/bb/index.php?threads/conve … aec-7726.38935/ to convert the CD acard adapters to HDD .

I think that's what feipoa means.

Yup. Which is hardly a ready to go solution unless you can unsolder surface mount chips, have access to a programmer, etc. etc. And even then no guarantees. I wonder how much would a run of ACARD ARS-2320 and ARS-2320S adapters would cost? Maybe a group buy could be arranged.

Shadow Lord wrote on 2025-03-13, 16:37:

weedeewee wrote on 2025-03-13, 16:11:

aliexpress & ebay are the standard go to Ultra-160 scsi ... was that the correct name? tired & needing to eat :-p […]
Show full quote

aliexpress & ebay are the standard go to
Ultra-160 scsi ... was that the correct name? tired & needing to eat :-p

https://68kmla.org/bb/index.php?threads/conve … aec-7726.38935/ to convert the CD acard adapters to HDD .

I think that's what feipoa means.

Yup. Which is hardly a ready to go solution unless you can unsolder surface mount chips, have access to a programmer, etc. etc. And even then no guarantees. I wonder how much would a run of ACARD ARS-2320 and ARS-2320S adapters would cost? Maybe a group buy could be arranged.

It's been a while since I've played around with them, but I recall someone messing about with the software to do a firmware update of the acard and managing to alter it in a way that the alternate firmware could be programmed via software.
Though, I haven't had time to try that myself.

weedeewee wrote on 2025-03-13, 17:09:

Shadow Lord wrote on 2025-03-13, 16:37:

weedeewee wrote on 2025-03-13, 16:11:

aliexpress & ebay are the standard go to Ultra-160 scsi ... was that the correct name? tired & needing to eat :-p […]
Show full quote

aliexpress & ebay are the standard go to
Ultra-160 scsi ... was that the correct name? tired & needing to eat :-p

https://68kmla.org/bb/index.php?threads/conve … aec-7726.38935/ to convert the CD acard adapters to HDD .

I think that's what feipoa means.

Yup. Which is hardly a ready to go solution unless you can unsolder surface mount chips, have access to a programmer, etc. etc. And even then no guarantees. I wonder how much would a run of ACARD ARS-2320 and ARS-2320S adapters would cost? Maybe a group buy could be arranged.

It's been a while since I've played around with them, but I recall someone messing about with the software to do a firmware update of the acard and managing to alter it in a way that the alternate firmware could be programmed via software.
Though, I haven't had time to try that myself.

It's been some time, but I recall reading that as well. Like you, I never bothered to look into it because with the wave of a $50 hot air station, the firmware can be swapped out. For the high performance systems (PII+), I went with NOS U320, for slower systems, I went with ACARD+CF. I also like the option of ACARD to also use it to convert IDE CD-ROMs to SCSI. I think I have at least one system which uses ACARD for HDD and for CDROM.