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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Motormouth on May 08, 2011, 03:57:03 AM
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Which is the better scsi card?
The IVS Trumpcard Pro
AMD 53c80 based
or the Dataflyer Plus without the IDE control
AMD 5380 based
I happen to have both scsi cards "lying around"
I wish I had a 4091 for the 4000, or better yet commodore could have put a scsi in the thing.
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They are both pretty crap.
Both are Zorro II without DMA and so offer no bandwidth or CPU load advantages over using the A4000's IDE.
Unless you've got a SCSI device you want to use... I'd leave them "lying around" and save electricity.
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They are both pretty crap.
Both are Zorro II without DMA and so offer no bandwidth or CPU load advantages over using the A4000's IDE.
Unless you've got a SCSI device you want to use... I'd leave them "lying around" and save electricity.
I partly disagree, I owned a IVS Trumpcard for my A2000 in 1993, and yes! it was flaky. Although some improvement came after I upgraded the rom.
I switched to The Expansion Systems Data Flyer Plus-SCSI/IDE combo board. It has ran flawlessly for 16 years until recently. However that is an issue with the PSU failing. Correct me if I am wrong but isn't even SCSI I still have a faster throughput than the early IDE channels found on classic Amigas? even with out the DMA, I could be all wet on this, it has been a long time in the classic Amiga hardware era for me. Maybe the later EIDE AtA 66, and ATA100 were better performers
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isn't SCSI still faster throughput than the early IDE channels found on classic Amigas? even without the DMA?
I don't think so. Both are PIO and both are 16-bit.
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I wouldn't use ether card in an A4000. You will hate the performance! Search for a 4091. It's worth the effort.
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They are both pretty crap.
Both are Zorro II without DMA and so offer no bandwidth or CPU load advantages over using the A4000's IDE.
Unless you've got a SCSI device you want to use... I'd leave them "lying around" and save electricity.
@motrucker I obviously would prefer a zorro III scsi card, or a scsi on an accelerator, but......
Would a zorro II DMA scsi card work any better? Would I need to install 16 bit fast ram to get DMA to work as some zorro II DMA cards default to PIO when transfering to 32-bit ram.
I have a GVP scsi card in one of my A2000s that I could switch out.
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@motrucker I obviously would prefer a zorro III scsi card, or a scsi on an accelerator, but......
Would a zorro II DMA scsi card work any better? Would I need to install 16 bit fast ram to get DMA to work as some zorro II DMA cards default to PIO when transfering to 32-bit ram.
I have a GVP scsi card in one of my A2000s that I could switch out.
there is no zorro II scsi card that will work better or faster than the A4000 motherboard IDE
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A GVP card with some RAM on it should work use the CPU far less than IDE. But if you have a fast CPU then it will be slower.
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A GVP card with some RAM on it should work use the CPU far less than IDE. But if you have a fast CPU then it will be slower.
And @Laserback
"there is no zorro II scsi card that will work better or faster than the A4000 motherboard IDE."
Darn, Yes this make sense, and is what I hypothesized.
Thanks, for all your help!!!
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I don't think so. Both are PIO and both are 16-bit.
I see your point, I was thinking SCSI I was 32bit. I just remember SCSI(at least SCSI II and III) was the preferred hard drive/interface for video editing and animation for a long time. I guess unless you have Zorro 3 SCSI II or III board, sticking to the IDE on an A4000 would be a better choice. That is unless you have SCSI devices that you really need to use.
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I am still a little confused at how and when the Amiga made use of PIO versus DMA, specifically with SCSI and IDE configurations. I remember it was always a big deal that the Amiga had DMA channels
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Where in the world are you? I came across a 4091 recently, but as it has not been used in about seventeen years I'm not sure it still works. You're welcome to it for the cost of postage.
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I am still a little confused at how and when the Amiga made use of PIO versus DMA, specifically with SCSI and IDE configurations.
The hardware must be DMA bus master (whereby the SCSI card initiates DMA transfers). The IVS Trumpcard Pro, Dataflyer Plus and Gayle IDE all do not support DMA of any kind.
I remember it was always a big deal that the Amiga had DMA channels
The Amigas DMA channels are between the custom chips and Chip-RAM. Gayle IDE does not have a DMA channel.
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I am correct in thinking that Zorro II does not offer DMA ?
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No.
Well, only to ZII memory.
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Well, only to ZII memory.
Yes I think this is true. A GVP controller with RAM for example has DMA. You must use the memory mask fields in the RDB to constrict the memory the SCSI driver will use.
Obviously this RAM is 16-bit and has a bandwidth limitation when used by a 32-bit CPU.
Some accelerators have their own 32-bit CPU, 32-bit RAM, SCSI controller and DMA controller to overcome these problems. (Cyberstorm for example.)
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I knew that the blizzard with scsi did DMA , and I figured that Zorro II didnt as I have never seen anyhting for Zorro II that did , well not Zorro II on my A1200 anyway.
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Basically DMA called is direct memory access can as it sounds can make transfers directly to memory. PIO mode stands for programmed I/O requires the CPU to get involved, taking CPU cycles. The problem with many zorro II DMA cards is they can only "DMA" to 16bit memory on a A3000 or A4000 the 32bit memory is at a different location. Some zorro II cards can DMA to 32 bit memory in an a3000 or a4000 but the transfer is only 16bit and can slow things down in other ways.
I have a habit having some 16bit fast ram, 2megs or more, in my a2000s and a500s even if I have a 32bit accelerator cards. This aids in DMA transfers on their respective the 16 bit buses. On A3000s or a4000s it is a bit of different story.
The A4091 is a zorro III card and can used the 32 bit bus.
I am still a little confused at how and when the Amiga made use of PIO versus DMA, specifically with SCSI and IDE configurations. I remember it was always a big deal that the Amiga had DMA channels
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@alexh
OK thanks for clearing that up. Is Gayle the IDE controller in AGA machines?
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Yes I think this is true. A GVP controller with RAM for example has DMA. You must use the memory mask fields in the RDB to constrict the memory the SCSI driver will use.
Obviously this RAM is 16-bit and has a bandwidth limitation when used by a 32-bit CPU.
Some accelerators have their own 32-bit CPU, 32-bit RAM, SCSI controller and DMA controller to overcome these problems. (Cyberstorm for example.)
I had a Phase 5 Blizzard 060 and SCSI II controller in my A1200, I wonder if controller was 32bit with DMA? I don't remember the specs. The SCSI board also supported 72 pin SIMMs like the 060 accelerator.
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I had a Phase 5 Blizzard 060 and SCSI II controller in my A1200, I wonder if controller was 32bit with DMA? I don't remember the specs. The SCSI board also supported 72 pin SIMMs like the 060 accelerator.
The ram was 32bit & supported dma. You wouldn't need to have a simm on the blizzard scsi board, it's just for extra ram expansion. But you would at least need some ram on the accelerator.
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The ram was 32bit & supported dma. You wouldn't need to have a simm on the blizzard scsi board, it's just for extra ram expansion. But you would at least need some ram on the accelerator.
Actually I think it was the Blizzard IV SCSI II controller, which according to "The Big Book of Amiga Hardware" was a 32 bit DMA able. At the time I had a 16MB SIMM on the accelerator and 4MB SIMM on the SCSI. That little 060 ran hot, I use to take the trap door off and raise it up about 1/2 inch for better air flow. I then aimed a house fan on the A1200 when I was rendering 3D animations. I sometimes wished I hadn't sold all of it.
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In order of preference:
- SCSI controller on your accelerator card.
- Zorro III DMA SCSI controller (A4091 or FastLane Z3)
- Zorro II DMA SCSI controller with some Z2 FastRAM (GVP HC+8/Oktagon 2008 etc)
- On-board IDE.
- Zorro II polled IO SCSI controller.
If you have a sufficiently awesome CPU card, you might prefer the on-board IDE to the Z2 DMA solution, but then again, any CPU card that's good enough probably has a SCSI option anyway.
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Is Gayle the IDE controller in AGA machines?
And in the A600, on the Viper A530 Turbo card, and re-created in the IDE68k addon.
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I knew that the blizzard with scsi did DMA , and I figured that Zorro II didnt as I have never seen anyhting for Zorro II that did , well not Zorro II on my A1200 anyway.
I have a Mediator card in my A1200, and my A4000. I just had an update from Darren Stevens for his device driver for certain PCI Adaptec SCSI cards, which now works for me with my Epson GT scanner, and as I have SCSI cards already in my A1200, and A4000, one on the accelerator, and one as an additional SCSI card, it offers me an additional 7 SCSI devices I can attach to each of my systems. With the Elbox Mediator pci.libabry RAM advantage of adding about 250MB of RAM from my PCI 9200 256MB Radeon GFX card onto my A1200 system FastRAM I've got close to 1/2GB of RAM, oh yes that's right almost HALF A GIGABYTE of RAM on a Classic Amiga.
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And in the A600, on the Viper A530 Turbo card, and re-created in the IDE68k addon.
and the viper520cd ;)
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Nearly-Right, Maybe you could exploit the RAM on the other computers by using it as an RAM-disc over SCSI by using the SCSI-bus ?