SCSI HD in A1200

I was thinking how would it be possible to add an internal SCSI Hard Disk to my A1200 which has the Blizzard SCSI addon. Of course, I would like to add a SCSI to SD converter and not a big scsi rotating hard disk.

The reason I am thinking of it is to get rid of the internal IDE which can do 1-1.5 mb/s but the SCSI device can do from 7mb/s to 10mb/s. Also, that device has DMA support, which I am sure will help a lot under heavy CPU usage.

Now, my questions are:
1. Would it be possible to boot from the SCSI disk? I guess that I will need to alter the Rom to do that, right?
2. Which SCSI to SD device would you recommend for internal installation?
3. What kind of cable would I need for connecting it on the Blizzard SCSI addon?
4. Has anyone done something like that and could share some ideas?

The Blizzard scsi-kit IV boots just fine from a scsi-disk.
I have had it for many many years but sadly it's been collecting dust ever since i moved away from using my A1200 in a tower because back then there was no good options to mount a drive internal.

Now time has changed and there is some options out there.
I have been looking at getting a bluescsi with external DB25 connector.

There's other versions out there so why with the external connector you might ask?
Well my scsi-kit was delivered with that kind of cable that could be attached to the scsi-kit, maybe you have that one too lying around somewhere if you bought it new?

It should be posible to place it somewhere inside the case, it will probably look terrible but i dont care.

@walkero
Quote:A SCSI to SATA converter and using a SATA SSD might be a better option, if you need a lot of disk space.
(Or a SCSI SSD, but there are probably only SAS SCSI ones, nothing for ancient SCSI controllers like the one used by the BPPC.)

Quote:You may have to enable it in the BPPC menu (hold <ESC> when booting), but a different ROM shouldn't be required.

There is no AmigaOS 4.x SCSI driver for the BPPC, only for the CSPPC, you can only use it on AmigaOS <= 3.9.

My initial plan for my A1200T back in the day was to expand via IDE, but after trying multiple expanders that simply didn't work I gave up and added a scsi kit to my Blizzard. It was more expensive, but a better decision as it was more expandable.

It worked fine, but with nothing on the internal IDE, took quite a while to boot up.

@daveyw
Quote:Something like https://amigakit.amiga.store/a4000-terminator-amiga-4000-p-831.html should be available for the A1200 as well.

@joerg

Thanks, haven't switched my A1200 on since 2020, if I resurrect it, I might get one.

Nice comments guys. Thank you for sharing.
This is something I would definitely like to test, so I am going to proceed and buy the needed parts. I will let you all know how it goes and if I experience any issues with it.
And also the benefits of switching to SCSI.
My only concern is how I will make them fit inside the A1200 case, where I have many other expansions. We will see.

Some update from me on the topic.

I got myself a ZuluSCSI Compact RP2040 https://store.rabbitholecomputing.com/ ... luscsi-compact-rp2040.htm
which is a scsi emulator, using a microSD. It is self powered from the Blizzard SCSI module with no problem.

My Blizzard SCSI module has 8.2 rom for now and booting from it is working fine. SysInfo reports that the SCSI speed is around 4MB/s with nothing else running, and I get something around 3.5MB/s when there is some CPU activity.

Having to deal with hard disk images is really convenient, since you can mount they on FS-UAE and do whatever you want with them, like transferring 3500 WHDLoad games.

I have a few further questions:
1. I use directscsi on it. Should it keep the speed of it standard, even under CPU usage?
2. In the partitions, do you recommend having 24bitDMA enabled on memory usage or keep it on Public (AmigaOS 3.2)?
3. Are there ways to speed it up more? In theory the Blizzard SCSI could reach 8MB/s I think
4. I am using FFS right now because when I tried SFS and PFS they didn't seem to work. For example, I couldn't SFSFormat an SFS partition because the tool either was freezing or crashed the system.

Thank you all for your help.

@walkero

Thanks for relaying your findings on this project. This is very cool. Would love to see a video showing your A1200 expansions as well as the setup in action.

@walkero
That zuluscsi seems nice, i want one!

Is the drive working in synchronous or asynchronous mode when benchmarking the drive?

If asynchronous you might gain alot of speed if you set it to synchronous.
The speed increase for me with a real scsi-drive was quite huge.

There is a tool to set the mode supplied in the P5 scsi tools disk that came with the scsi-kit.

@smf
Quote:
I haven't tested that at all. Thank you for your recommendation. I will check this out and report back.

@walkero

Have plenty of Phase 5 accelerators from 1230, 1240, 1260 and BPPC.

Something to take note when using the phase 5 scsi.

The 1230 to 1260 can utilise the MKIV SCSI add-on. To get the best out of the SCSI the highest CPU should be used.

Software wise, make sure you get get hold of and install the Phase 5 SCSI software which can be had from here;

http://phase5.a1k.org/

This will allow you to utilise asynchronous and synchronous modes via software.

Also recommend this tool and place it into your startup sequence

http://aminet.net/package/util/misc/MyUnitControl

That way you can implement synchronous and high speed SCSI speeds on startup.

Reviving an old thread…

I had the same idea some time ago, to have an internal SCSI drive in my desktop A1200 with Blizzard SCSI Kit, but I didn't want to lose the possibility to connect external devices, so what I did is to make a new cable:

SCSI Kit connector ==> Internal DB25 ==> External DB25 (the original one)

Both DB25 connectors are female, and usually devices have male ones, but it's a wise decision to have some DB25 gender changers (male-male), just in case, some devices have the other gender, or you need an adaptor with the other gender (SCSI2SD needed a IDC50 to DB25 adaptor, and the DB25 in the adaptor was female, so a gender changer was mandatory).

So, whatever I connect to the internal one, inside the A1200, it has the termination set to OFF, so I can connect external devices on the rear DB25 connector. I have external HDs, a ZIP drive, several 2GB Jaz drives, a tape drive, a scanner, optical drives, even a SCSI 3"1/2 floppy drive from a SGI…

I have tried internally a SCSI2SD, a ZuluSCSI RP2040 and a SCSIknife Multi, all three work well.

You may wonder what happens if termination is set to OFF and i don't connect anything to the external one, problems may arise (even if I have never faced a single problem with only one device connected in 30 years), or else I should open the A1200 lid and change termination: I have an external DB25 terminator ( https://i.imgur.com/LAXOMja.jpeg ), so when nothing else is connected, I plug the terminator. Solved.

Now I want to try an internal BlueSCSI v2 with a RPi Pico 2W, it has WiFi, a nice and useful feature, and I'd like to give it a go. The problem with these small devices, this one and the ZuluSCSI Slim Pico, both designed to be external, the last device, is that both have termination forced to ON by design, you cannot change it. Fortunately, a friend with knowledge in electronics tweaked the BlueSCSI v2 DB25 and redesigned it, taking out the soldered termination resistances and placing holes for a socket for two resistive grids that do termination, like in the old hard disks, so you can connect them or not depending on the use. When internal, they will be unplugged, but I will be able to use it as external too just plugging them in its place.

Saluditos,

Ferrán.

@Ferry

Can you check your signature links? They don't work.