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Compact Flash in se/30

Are there issues with the number of rewrites?

Yes, I forget exactly what the theoretical number of re-writes is....however they are designed to be used as HD's for 'industrial' purposes and therefore have a higher rating than your average standard flash card. In our case with the XPe system once we load the OS onto it, it never has to write to that drive again (we have a standard HD for all the other data files)

As a side note, I always find sentences with "it it", "that that" and "had had" very amusing. Sometimes there is no other way to write the sentence

 
Kallikak & Flash!, perhaps you two gentlemen could persuade your fellow countryman, Greg Ewing, to pursue a SCSI Flash hack!
Going by the URL I'd say that Greg is a kiwi (a person of New Zealand persuasion is called a kiwi) and whilst it is a common myth that NZ is part of Australia there are several million people in this part of the world who beg to differ! In fact it could be said that Australia is part of NZ.... NZ is made up of islands, the main ones being inventively named The North Island, The South Island, Stewart Island, and West Island - the west one being Australia [:D] ]'>

Now just to throw a spanner in the works, I am actually a kiwi.... I have been living in Australia long enough to lose my kiwi accent, but not long enough to call myself an Australian. Besides, the All Blacks kick the Wallabies ass 95% of the time (sure Aussie won the world cup....but can you say Bledisloe Cup!?!?!) and I don't want to be a member of a country that can't play footy [:o)] ]'>

 
Kallikak & Flash!, perhaps you two gentlemen could persuade your fellow countryman, Greg Ewing, to pursue a SCSI Flash hack!
Not a simple hack at all, as the Compact Flash I/O format is already basically IDE.
 
True, SCSI wouldn't be a simple hack relative to IDE. But upon reading through Mr. Ewing's work, I can see he is no simpleton either. Indeed, he appears to me to be energized by a challenge, especially one that produces a useful tool or toy in the end. Such would be the case for a SCSI flash drive -- something that would be wildly popular among classic Mac owners such as ourselves.

But despite all this, keep in mind my post above about remapping (rewrites and lifespan of the flash). Even if Mr. Ewing were to create a hack for us, it is unlikely to involve the level of detail that most SSD's have built-in.

 
I recommend the Adtron SDDS SCSI PC card drive (3.5 inch form factor, 5 V supply voltage). (Search for "Adtron" in the forum.) I have one in use for a while now as a boot device for a Performa 475. It performs very well with a Kingston 1 GB (100x), little difference compared to the original harddisk drive. The drive probably could be installed in place of a floppy disk drive, to swap media without need to open the case. I am not very familiar with early compact macs. Probably an unused expansion slot has enough space to allow the drive to be mounted without removing the original drives, with access from the rear side of the mac. The drive itself is pretty shallow, it is only the bezel that blows it up to the size of a 3.5" FDD. Suppliers can be found, still, but prices may vary anywhere (!) up to USD 400 (ouch) plus shipping and tax -

 
There are a number of cheap desktop PCMCIA adapters on ebay that come with a PCI or ISA SCSI card. These should work.

There are others that come with a card that uses a 40 pin cable, which might be IDE or some proprietary connection. Also, there are external units like this one that use a parallel port connection, easily confused with SCSI. In addition, some of the SCSI ones have limitations on the size of the flash cards they can read. Caveat emptor

 
register, thanks for bring this to our attention. I checked out the Adtron product page and I see that it is indeed a SCSI flash drive. So the questions then become:

1) What is the voltage and current requirements? Obviously, we wouldn't want to run that AC adapter cord outside the Mac, and I'm not sure we'd want to tap the 110VAC to keep the adapter inside. Therefore, we would need to know the voltage/current requirements to determine how best to power this. If it works on 5v or 12v, then the HD power connector that's already available in the SE/30 would be perfect.

2) What is the exact cable adapter we would need to match the internal SCSI cable of the SE/30 to the SCSI-2 connector on this flash drive?

3) Can this drive truly boot the SE/30?

4) Are there any incompatibilities? (i.e., no Utility software will work, etc.)

 
This is some information about the Adtron SDDS SCSI PC card drive (3.5" form factor).

1) What is the voltage and current requirements? Obviously, we wouldn't want to run that AC adapter cord outside the Mac, and I'm not sure we'd want to tap the 110VAC to keep the adapter inside. Therefore, we would need to know the voltage/current requirements to determine how best to power this. If it works on 5v or 12v, then the HD power connector that's already available in the SE/30 would be perfect.
The supply voltage is 5 Volts DC, max. current 1 Ampere. The power connector is a standard 4 pin Molex type, like in any 3.5" harddisk drive. There is a DC/DC converter on board to source PC cards which require a higher supply voltage (this might be a hint towards a possible use of this device inside a PowerBook; but do not expect to use any other cards than storage devices.)

2) What is the exact cable adapter we would need to match the internal SCSI cable of the SE/30 to the SCSI-2 connector on this flash drive?
The board has got a standard 50 pin male connector, slotted, for use with an usual IDC connector for internal SCSI drives (I would call "usual" what I have seen inside any LC up to beige G3). Termination ON/OFF may be set with a jumper, as well as the SCSI ID number. There is a jumper to "disable disconnects", also.

3) Can this drive truly boot the SE/30?
I have verified the drive to be completely operational as a boot device for a Performa 475 (HFS/Mac OS 8.1) and a beige G3 (HFS+/Mac OS 9.2.2). It works well with several different types of Flash storage cards inside the PC-card slot (PC-Card, CF within a PC-card-adaptor, SD within a PC-card-adapter).

As I have no SE/30 to perform a test, I can not tell if it will work for this machine. If there are justifiable doubts wether it could work, I might try to find one and check this.

4) Are there any incompatibilities? (i.e., no Utility software will work, etc.)
The Apple drive setup seems not to work for this drive, not if ResEdited the usual way, also. FWB Hardisk Toolkit works just fine. I avoid possible problems just by formatting the PC-card in the slot of a PowerBook running Tiger, using the latest version of Disk Utility.

I have only tested consumer grade CF-cards up to now. Industrial grade CF cards should work anyway. Be aware of known incompatibilities of recent SD cards with not so recent PC-card-adaptors (_High Capacity SD_).

Other details are: The front bezel of the drive shows a pushbutton to eject a PC-card (sorry, no auto eject mechanism). It also has a two colour LED, showing green light when powered and idle, orange when busy, no light when off ;-)

If you strive for better access to the PC-card slot: the adaptor fits well into an external enclosure for 3.5" removable media drives (like the small Syquest or ZIP drives).

In case of need for more detailed information, just ask.

 
Check this out. I found a retailer offering SCSI PCMCIA drives for use with samplers. They're a little pricey for me, but might be suited to some here.

From experience, I can tell you that if it works on a sampler, it'll work on a Mac and vice versa. Zip drives excepted.

There's also this, from my fritter blog:

Now this is interesting: this fellow has built himself a SCSI RAM-disk and a SCSI PCMCIA drive from scratch, using AVR microcontrollers. I wonder if this could be a starting point for further SCSI-to-X hacking.
 
Um, the website reports EOL. I did a Google search and turned up no vendors. Assuming it will work on an SE/30, how exactly does one go about obtaining one?
There is a German supplier that might have devices similar to the Adtron SDDS in stock. Got to http://www.apdate.de and look for

S35P-C03N-101

Adtron PC Card SCSI Drive, 1 Slot

or

S35P-C01N-101

Adtron PC Card SCSI Drive, 2 Slots

But fasten your seat belts securely before you ask for a price. Keep in mind this is stuff intended for military use, originally.

What about this instead? Adtron SDDS Cardpak™ PC Card Drive. – it could be mounted in the FDD bracket and CF cards inserted through the floppy slot.
This thing looks very similar to the SDDS I referred to. If you obtained one, it should be fine.

This might be the best solution if there would not be an issue with the price. Drives like this are optimised for reliability and performance as well, to be used in aviation and spacecraft appliocations. You will not have the option to replace defective flash memory in this drive, though. That would be the benefit of obtaining a card drive for standard CF cards, only. A CF card that exceeds the rated number of writing cycles could be replaced for a fraction of the price of a real solid state disk.

A used one would be nice, but a drive like this in professional use will be replaced only after some heavy usage, I think. So I would not pay much for a used one.

Check this out. I found a retailer offering SCSI PCMCIA drives for use with samplers.. They're a little pricey for me, but might be suited to some here. From experience, I can tell you that if it works on a sampler, it'll work on a Mac and vice versa.
The device shown in the picture provides the same functionality as the Adtron SDDS. I can not identify the brand. The board layout looks different to the device I use. The price seems to be fine, compared to other sources, because you get the device ready to use with an enclosure.

 
I was thinking of doing a CF project but decided against it. Even though CF drives are quieter, faster and cooler they don't have enough read/write cycles in them to make them reliable enough for long term use. I don't like the value equation of solid state drives but think they would be a better choice since they are designed to be used as hard drives. CF cards generally aren't, even high performance ones. I might consider a micro-drive, though.

 
Even though CF drives are quieter, faster and cooler they don't have enough read/write cycles in them to make them reliable enough for long term use.
The numbers really mean very little to me, but I've heard from so many places that this is not an issue anymore... and if used with an OS that doesn't swap...

 
Even though CF drives are quieter, faster and cooler they don't have enough read/write cycles in them to make them reliable enough for long term use.
CF cards are not intended for reliable long term use in the first place. You might better think of something like a ZIP drive to compare with. But CF cards are pretty cheap, and the smallest number of _write_ cycles I read about was 10k. The number of read cycles seems not to be a limiting factor in practical use. In fact I had a lot of defective removable disk drives and media (may it be ZIP, Bernoulli, Syqest, CD, Floppy or any else), but even the oldest CF devices I have do work well, still.

A micro drive for use as a replacement for a standard hdd would give you the benefits of a small footprint, low power consumption and fast writing access. It would combine the disadvantages of both CF cards (less reliable) and usual harddisk drives (moving parts), also.

I think your choice should depend on the use you expect to have for the device.

- For frequent use with heavy writing load, where writing access performace is of importance, have a SCSI-IDE converter in combination with a new silent IDE harddisk (available in 2.5" and 3.5" varieties).

- If your system has no fan and you need it to be even quieter than a modern silent harddisk but with top performance, have a solid state disk or an industrial grade dual CF adaptor with two CF cards in striping RAID mode (level 0).

- In any other case a recent CF card in an appropriate adaptor should do well in a vintage machine. (Do not use this drive for virtual memory.)

- If price matters (as it usually does), you might consider an external SCSI enlosure with a long cable, hiding away the drive in a place where it is allowed to be noisy, and use up used server harddisks (SCSI). You might have to throw in a few extra bucks for a recent SCSI-a-lot-pins to standard SCSI adaptor, but gain a cheap supply for high speed drives. This especially applies to people with access to server farms, where usable drives get swapped for new ones based on a fixed schedule.

- And, a more hypothetical case, if the price should not matter at all, have an UPS buffered RAM-disk and stream the contents to a NAS.

In any case you always should have a working backup of your important data ;-)

 
The read/write cycle limitation is certainly real, but it is not nearly as serious a problem as most people seem to think. Modern flash employs sophisticated wear-leveling strategies to avoid cycling any one bit (or group of bits) excessively, as well as automated self-repair (using spare "sectors"). Consequently, there are relatively few practical scenarios where one would encounter failures due to cell wear-out. Overall, the MTBF of a modern flash drive is about the same as that of a hard drive. Indeed, in some cases, it's far higher.

 
I might consider a micro-drive, though.
Don't. I tried one in my Newton (via the ATAsupport driver) and found it to be horrible. The problem with MicroDrives is that they spin up and down constantly. This is not a major problem when used in a digital camera, but it is a serious problem when used in anything else (like a Newton or Mac). Just imagine if your regular hard drive spun up and down continually every few seconds. It almost becomes unusable it's so slow.

With flash, you don't have to worry about spin-ups or spin-downs.

 
I might consider a micro-drive, though.
Don't. I tried one in my Newton (via the ATAsupport driver) and found it to be horrible. The problem with MicroDrives is that they spin up and down constantly. This is not a major problem when used in a digital camera, but it is a serious problem when used in anything else (like a Newton or Mac). Just imagine if your regular hard drive spun up and down continually every few seconds. It almost becomes unusable it's so slow.

With flash, you don't have to worry about spin-ups or spin-downs.
Eh, never heard of that before. The MicroDrives in iPod Minis certainly don't do this... sure it's not to do with the newton ATA driver?

 
sure it's not to do with the newton ATA driver?
How can I? Other than my camera, I have no other means to use the MicroDrive. But I can say that I hear it spin up and down in my camera too. But then again, my camera doesn't write date to the drive for extended periods of time either.

So clearly, someone else needs to confirm my findings with a method other than a Newton or digital camera.

But even if someone finds that the Microdrive doesn't spin up and down "as much" as I have found, the fact remains there will be spin ups and downs as the Microdrive is not made to spin constantly forever.

 
I've read this thread with great interest, as for some time I've been considering the options for a software-based (FWB Hard Disk Toolkit 3.0) RAID 1 array in a heavily upgraded SE/30 (accelerator, video card, RAM, etc.) utilizing the best overall storage technology. This was discussed thoroughly prior to the tragic forum data loss of early 2007, with valuable contributions by JDW and TylerEss, among others. A couple of criteria are that the primary performance concern is access time and at least one of the two drives (and preferably both) must be installed inside the machine so that the HDD activity light can be attached.

I'd largely settled on solid state drives due to their silence, low power usage, and SCSI interface (to preserve the SCSI chain's "purity" and thereby avoid the latency of a bridge chip). Late last year I found a relatively reasonably priced supplier that doesn't charge at mil spec levels (as Adtron and many others do), but have been hoping for further price drops (plus no one offers 2.5-inch SSDs with the appropriate interface any longer, so I'd either have to Velcro two 3.5-inch drives together--they're relatively thin--or place one in an external enclosure).

Now I'm intrigued by the idea of using either SCSI-CF adapters or SCSI-IDE + IDE-CF combinations, along with flash cards, for a few reasons: significantly lower cost, long-term availability, and in particular the ability to replace a CF card should one wear out while still preserving the adapter(s) investment. If I forgot to disable virtual memory for an SSD, the financial hit borders on being exponentially higher than with a CF card.

My concern with using CF over SSDs is performance. Yes, I'm aware that the bus on these old machines is quite limited, but as others have noted faster HDDs do make them feel more snappy, so I wonder whether there would be a noticeable difference between CF and SSDs, especially in access time. In the past I asked Manabu (artmix.com) whether his PowerMonster RX (SCSI-IDE adapter) with a 7200 RPM HDD or CF PowerMonster with CF card would be the faster option, and he indicated the former--that a modern HDD would be faster than CF. The lowendmac user review of the CF PowerMonster referenced above indicates that performance was comparable to a hard disk drive, but not whether the drive being compared to CF is 5400 or 7200 RPM.

I have noted register's great post above delineating usage-based recommendations and an earlier relevant post by JDW, but my concern is more specific. Here are the questions that this post suggests:

1) Keeping in mind the limitations of the SE/30 SCSI bus (1.25 MB/sec), which would provide faster perceived access times, SSD or CF?

2) Would it be enough of a difference to at least somewhat justify a significantly higher cost?

3) If CF is recommended, is there any advantage to one adapter choice over the other (SCSI-CF or SCSI-IDE + IDE-CF combination)?

4) Again, if CF is recommended, would the industrial grade adapters provide better performance than what artmix.com offers? He doesn't provide specs, as we know.

I'm not concerned with having the fastest specifications, just the fastest file access and application loading that I can perceive in real-world usage.

Incidentally, the Adtron products referenced earlier by register are available at WDL Systems but are designed to be installed in a 3.5-inch bay. Thus, they have LEDs on their faceplate, not pins for the activity light as on compact Macs, which knocks them out of consideration in my case--unless perhaps the LED connection could be hacked for compact use (though I'm averse to doing that).

 
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With the low power-draw of the CF cards, I think one could do RAID 1 inside the SE/30 and sleep a little more soundly at night. Remus RAID will do RAID on the onboard SCSI of the SE/30, despite it not being SCSI Manager 4.3 compliant.

Of course, this would require the purchase of TWO SCSI-IDE adaptors, unless someone knows of one that supports both master and slave. The acard SCSIDE chip supports dual devices, but I don't think the adaptors do.

I'm considering making a run of SCSI -> Dual CF adaptors for use in old computers like these Macs, but it depends highly upon how expensive the acard SCSIDE chips cost. acard hasn't returned my email yet.

I don't think there's likely to be any huge performance difference between the CF and the dedicated SSD: the difference between an ancient hard drive with 20 or 30ms access time and newer drive with 7ms access time is about 33% reduction in boot-time. I'm guessing that a further reduction into the 2ms range will bring improvment, but not dramatic improvement. Until someone benchmarks a CF-mac against an SSD-mac, we'll never know for sure!

 
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