Apple II Hard Drives and SCSI Interface Manual

 

Csa2 FAQs-on-Ground file: CSA2HDNSCSI.TXT rev010

 

 

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____________________________

 

 

 

001- How difficult is it to add a hard drive to my IIgs?

002- What kinds of hard drive systems are available?

003- What do SCSI ID numbers mean?

004- What is "SCSI-2" and how is it different from SCSI-1?

005- Will a SCSI-2 hard drive work with an Apple II system?

006- Will my Rev. C SCSI Card work with a SCSI-2 drive?

007- What is SCSI "termination power"?

008- Can I avoid the "RamFAST/SCSI is searching SCSI bus" delay?

009- What is the pin-out for the standard 50-pin SCSI cable?

010- What's the SCSIHD.DRIVER patch to ignore DRIVER43 partitions?

011- What is the "bad bug" in the ROM 3.01e RamFAST?

012- What are correct HS SCSI settings, etc. for a Bernoulli drive?

013- What are the settings for a CMS hard drive controller card?

014- Does it matter when I power-ON my SCSI hard disk?

015- Can I leave SCSI devices I'm not using turned OFF?

016- Is there a generic SCSI tutorial available for downloading?

017- What is the correct time-out setting for a Focus hard drive?

018- How do I modify my Apple HSS card to supply Termination Power?

019- Can I get a Focus drive bigger than a couple hundred MB?

020- My hard disk is on a CMS SCSI. How do I install System 6.0.1?

021- How is DMA set for SCSI cards with 8MB RAM cards on the GS?

022- My 20MB Focus bombs and there's some goo on the card. A fix?

 

 

 

 

 

 

From: Bradley P. Von Haden

 

001- How difficult is it to add a hard drive to my IIGS?

 

Adding a hard drive is not much of a problem. Usually, you will need to

insert an interface card, possibly connect a cable or two, and change a

Slot setting in the Control Panel Desk Accessory.

 

---------------------------

 

 

002- What kinds of hard drive systems are available for Apple II

users?

 

The most versatile and most common hard drive set-up is an internal

SCSI interface card and an external SCSI drive. Hard drives, cd-rom

drives, removable media (SyQuest, Iomega), flopticals, and scanners all

can be added to the SCSI chain. Insert the card in a slot, connect a

cable or two, and change a slot setting.

 

The preferred SCSI card is the RamFAST Rev. D SCSI card from

Sequential Systems. The next best card is the Apple Hi-Speed SCSI card.

 

Here are some RamFAST notes:

 

- still being produced and supported by Sequential Systems

- faster than Apple Hi-Speed, especially in ProDOS

- provides termination power to the SCSI chain

- allows partitions to be mapped in ProDOS

- device drivers come on the card in the upgradeable ROM chip

(3.01f)

- allows up to 8 devices to be added to the chain

- allows up to 12 partitions to be active at any one time

(switchable)

- allows up to 12 partitions per drive

- about $130 new

 

 

Here are some Apple High Speed notes:

 

- no longer produced or supported by Apple

- does not provide termination power to the SCSI chain (can be

modified to provide termination power)

- does not allow partitions to be mapped in ProDOS

- device drivers are software

- allows up to 7 devices to be added to the chain

- allows over 100 partitions to be active at any one time

- allows up to 20 (?) partitions per drive

- about $110 new (if still available)

 

 

For the hard drive itself, look for a SCSI drive in an external

enclosure with the following features:

 

- 30 day money-back guarantee

- external SCSI ID switching

- dual 50 pin SCSI connectors

- no or switchable termination (use an external terminator at

end of SCSI chain)

- switchable termination power (on/off) is a plus for users of

SCSI interface cards which do not supply termination power

 

---------------------------

 

 

From: Rubywand

 

Another way to go is a 2.5" IDE drive mounted on an IDE interface

card. This "hard card" plugs into a Slot-- usually Slot 7. Alltech sells

the Focus Hard Card in varying sizes (e.g. 60MB for $99) with system

software installed. SHH Systeme offers the FileCard (about $170 + cost

of drive) as well as a series of IDE controller cards to which you can

add a 2.5" IDE drive (about $120-$170 including mounting kit).

 

The IDE hard card approach offers speed and capacity comparable to

SCSI, very easy installation, and, it eliminates hassles with external

boxes and cables. Of course, you will still need to add a SCSI interface

card if you want to connect a SCSI CD-ROM and/or Zip Drive.

 

Note: If you want your system to include a SCSI CD-ROM drive, it is best

to have a SCSI Zip Drive or SCSI hard disk connected to the SCSI

interface, too. This provides a write-able medium for saving SCSI

interface card setup parms.

 

____________________________

 

 

 

From: Rubywand

 

003- What do the SCSI ID numbers mean?

 

SCSI ID numbers identify devices on the SCSI chain. Each device

should have its own, unique ID number in the range 0-7. (If two devices

on the SCSI chain have the same ID number, there will be a conflict and

your system will not function correctly.) Higher numbered devices have

higher priority-- get 'looked for' first-- so, it is standard practice

to set the device you boot from to 6 or 7.

 

Most external SCSI devices have a thumbwheel switch, slide switch,

or jumper block on the back to set ID number. Some, like the Creative x2

CD-ROM drive let you click through 0-7. The Zip Drive lets you pick 5 or

6. (By the way, SCSI ID numbers have nothing to do with which Slot the

SCSI interface card is in.)

 

---------------------------

 

 

From: David Empson

 

SCSI ID 7 is usually special because the Apple SCSI and Hi-Speed

SCSI cards count as a device set to ID 7 by default (and every Macintosh

has a hard-wired SCSI ID of 7). The only thing that is special about ID

0 is that it is the standard ID used for an internal drive on a

Macintosh.

 

There is no problem using SCSI ID 0 on an Apple II. On a RamFAST

SCSI card, it is also safe to use SCSI ID 7 for a drive. The RamFAST

doesn't have a SCSI ID, but every other SCSI card does.

 

 

___________________________

 

 

 

From: David Empson

 

004- What is "SCSI-2" and how is it different from SCSI-1?

 

For hard drives, "SCSI-2" basically means that the drive supports a

stricter command set. The physical interface is usually identical.

 

For other device types, "SCSI-2" means a lot more, because the original

SCSI standard didn't define much in the way of device types and command

sets, so most devices use proprietary command sets. SCSI-2 standardises

the command sets for most types of devices.

 

There are three special types of interface that you might see mentioned:

 

"Fast SCSI" supports data transfer at twice the speed of the original

SCSI standard (10 MB per second vs 5 MB per second). This will not be

a compatibility issue, as it is just the maximum transfer speed

supported by the drive. The Apple II cannot transfer more than one

megabyte per second.

 

"Wide SCSI" uses a different cable arrangement to double the width of

the data path (16 bits instead of 8 bits). A wide SCSI drive cannot be

used with an Apple II, unless it can also operated in "narrow" mode

with the original 50-pin connector. (There is also "Fast Wide SCSI",

which doubles the data rate and the width of the bus.)

 

"Differential SCSI" involves a different type of interface to the

computer, where every data signal has a balanced positive and negative

pair of wires, rather than a single wire and a ground line. I believe

it has a different type of connector. Differential SCSI drives cannot

be used with an Apple II."

 

Some drives use a proprietary connector, but the standard (narrow,

non-differential) SCSI bus uses the same 50-pin connector for SCSI-1 and

SCSI-2.

 

The only significant problem you might run into is termination, and

supply of termination power. SCSI-2 devices tend to be fussier about

termination than older devices.

 

------------------------------

 

 

005- Will a SCSI-2 hard drive work with an Apple 2 system?

 

Usually, yes. I'm on my second Quantum drive that is described as

"SCSI-2".

 

There is a major caveat to this answer. Some newer drives require

a host which implements the arbitration phase of the SCSI communication

dialogue. The RamFAST doesn't do this, and as a result there are some

drives that cannot be used with a RamFAST SCSI card. A notable example

is the Quantum Fireball series. However; the Trailblazer and all older

Quantum models work fine.

 

 

 

------------------------------

 

 

006- I have a plain ol' Rev. C SCSI Card, will this work with a

SCSI-2 drive?

 

My Quantum LPS240 is working fine on an original Apple SCSI card.

 

Note: With the original Apple SCSI card, the card itself is not

terminated, so if you are connecting more than one device, you need to

add a second terminator between the computer and the first drive (using

a "pass-through" external SCSI terminator, or internal termination on

the first drive).

 

 

------------------------------

 

007- What is SCSI "termination power"?

 

At least one device (SCSI card or any SCSI drive) must provide

power for the SCSI terminators by feeding 5 volts onto the TERMPWR line

on the SCSI bus.

 

Usually, termination power is fed through a diode to prevent

backfeeding from a higher voltage source in case some other device is

also supplying termination power. A good implementation will have a fuse

to protect against shorts and a capacitor to cope with a sudden rise in

termination power drain.

 

The Apple SCSI cards do not provide termination power (though some

recent Apple Hi-speed SCSI cards were modified by Apple to provide

termination power). The RamFAST SCSI card can supply termination power.

 

If a drive can supply termination power, I recommend letting it do

so. The TERMPWR line can, in some cases, represent a significant load on

the +5V rail going to the Slots. Both of my Quantum drive mechanisms

provide termination power to the SCSI bus, avoiding the need to supply

it from anywhere else.

 

----------------------------

 

 

From: Rubywand

 

On the RamFAST SCSI RevC card, DIP switch #1 is set to ON to supply

termination power. On other RamFAST SCSI cards, a jumper is placed at

JP1 to supply termination power.

 

According to RamFAST documentation, it is okay to have the card set

to supply termination power whether or not another device does with a

few notable exceptions. If a connected hard disk (e.g. a Sider drive)

has a sticker saying that the drive supplies termination power and that

the interface must not, then the RamFAST must be set to _not_ supply

termination power.

 

____________________________

 

 

 

From: LJSilicon

 

008- I just reinstalled System 6.01. Now every time I cold boot

I get this message 'RamFAST/SCSI is searching the SCSI bus

for devices..etc.' and have to wait several seconds. WEIRD?!

 

When you reinstalled the software, the RamFAST set itself for a

long search. This is an option that you can change using the RamFAST

utility. What it is doing is giving your scsi devices a chance to spin

up. If you want a fast check, go to the options menu on the utilities

and reset the Short Timeout option there to "YES".

 

 

__________________________

 

 

 

From: David Empson

 

009- I would like to make my own SCSI cable. Does anyone on csa2

know the pin-out for the standard 50-pin SCSI cable?

 

The cable pinout is documented in the technical reference manual

for the Apple High-Speed SCSI card (and the original one as well).

 

This pinout is not a simple mapping from one end to the other.

 

I repeat that it is NOT easy to make one of these yourself. Apart from

any issues of wiring errors, you also need a properly shielded cable to

minimise noise being picked up or radiated. You should definitely not

use a ribbon cable.

 

Here is the pinout, assuming I haven't made any typos (I can't see any).

 

DB-25 50-pin Function

 

1 49 -REQ

2 46 -MSG

3 50 -I/O

4 45 -RST

5 44 -ACK

6 43 -BSY

7 16,18,19 Ground lines

8 26 -DB0

9 20,21,22 Ground lines

10 29 -DB3

11 31 -DB5

12 32 -DB6

13 33 -DB7

14 1,2,3 Ground lines

15 48 -C/D

16 4,5,6 Ground lines

17 41 -ATN

18 7,8,9,11 Ground lines

19 47 -SEL

20 34 -DBP

21 27 -DB1

22 28 -DB2

23 30 -DB4

24 23,24,25 Ground lines

25 38 TERMPWR

 

The unlisted pins in the 50-pin connector (10, 12, 13, 14, 15, 17, 35,

36, 37, 39, 40, 42) are ground.

 

Note: the numbers for the 50-pin connector are counted along each row,

like a DB-25. They are NOT the wire numbers in a ribbon cable.

 

____________________________

 

 

 

From: Steve Reeves

 

010- Is there some patch for SCSIHD.DRIVER to make it ignore

APPLE_DRIVER43 driver partitions?

 

Yes; you can change the counter in the string comparison routine

that checks for the "Apple_Driver" partition type string so that it only

checks the first 12 characters. This counter is at byte $3574 in the

System 6.0.1 SCSIHD.DRIVER file and is originally $1F. Change this to

$0B and the driver will then ignore "Apple_Driver43" partitions.

 

If you make this or any other patch to the driver, I also you

recommend you bump up the version number. Change byte $01FF from $10 to

$2E (for version 6.02 experimental).

 

____________________________

 

 

 

from Harold Hislop

 

011- Someone told me there's supposed to be a bad bug in the

ROM 3.01e RamFAST. What is it?

 

Don't use the built in backup/restore in 3.01e!!! The restore

opeation will nuke the partition map on the drive being restored to, as

well as all existing partitions on that drive!

 

 

____________________________

 

 

 

From: Bradley VonHaden

 

012- What are correct HS SCSI settings, etc. for a Bernoulli drive?

My system is as follows:

ROM 1 Apple //gs

4mb AE RAM card

8mhz ZIP GS

Apple High-Speed SCSI card

90 mb Bernoulli hard drive

System 6.0.1

 

 

Three things I can think of to check:

 

One possibility is DMA compatibility. If your memory card is not DMA

compatible, then switch 1 on the Apple HS SCSI card should be open (up).

 

Another possibility I guess is a SCSI ID conflict. The Apple HS SCSI

card's ID at the factory is set to 7. Here are the Apple HS SCSI card

switch combinations:

 

note1: Switch 1 controls DMA; open (up) turns DMA off

note2: Switches 2-4 control SCSI card ID

note3: 'U' means open (up), 'D' means closed (down),

'z' means Set for correct DMA (see note1)

 

SWITCH: 1234 1234 1234 1234 1234 1234 1234 1234

SETTING: zUUU zUUD zUDU zUDD zDUU zDUD zDDU zDDD

CARD ID: 0 1 2 3 4 5 6 7

 

Third, the scsi chain needs termination power to work properly. This is

different from termination. Both are required for a properly

functioning scsi chain. It is possible that neither the Bernoulli drive

nor the Apple HS SCSI card is supplying termination power. If this is

the case, and there is no other device on the scsi chain to supply said

power, it probably won't work. There is a modification (requires

soldering skills) to the Apple HS SCSI card to make it supply

termination power.

 

____________________________

 

 

 

From: Jack Countryman IAC

 

013- I want to configure a CMS hard drive controller card to run a

20 meg drive for a //e. Could someone supply info on settings?

 

According to the CMS manual, page D3, the six sets of eight pairs

of jumpers

(u1....u6) are for the following purpose:

_______________________________________________________________

/ |

/ u 1 u 2 u 3 u 4 j2 |

/ |

/ |

| |

| |

| |

| |

| |

| u 5 u 6 |

|___________________________________________ j1 |

| |

|______________________|

 

 

u 1: Boot Scan delay....manual shows no jumpers here in default

configuration

 

u 2: first (left) jumper is 'Enable I.C.P. (Yes/No)', middle 6 not

used, last (right) is 'multiple initiators (Yes/No)'...manual

shows no jumpers in default configuration

 

u 3: Selection phase time out delay....I believe this sets how long

the card waits for the drive to come up to speed(?)...manual

shows the default as having 4, 5, and 7 with jumpers installed

 

u 4: Arbitration phase time out delay....manual shows default as no

jumpers installed

 

u 5: Bus Free phase time out delay...manual shows default as jumper

on number 1

 

u 6: Interrupt recovery delay....manual shows jumpers on 3, 4,

and 5

 

 

J1 and J2 are single sets of pins. The manual says J2 is not used,

but J1 is to be jumpered.

 

 

The card I have here, came out of a IIGS where it was hooked to

first a twenty meg CMS drive, and later a forty meg CMS drive. It has

the following jumpers set:

 

u1: jumper on 7

u2: no jumpers

u3: jumpers on 4, 5, and 7

u4: no jumpers

u5: jumper on 1

u6: jumpers on 3, 4, and 5

j2: no jumper

j1: jumper

 

 

As I recall, this setup yeilded a rather long pause for the hard

disk to come up to speed (about 40 to 45 seconds) that we found

necessary at the time to avoid boot problems.

 

____________________________

 

 

 

From: B.J. Major

 

014- Does it matter when I power-ON my SCSI hard disk?

 

From the Apple IIgs Owner's Reference, page 267:

 

 

"In order for the Finder to recognize a hard disk, the hard disk must be

switched on and up to speed before you start up (or restart) the

computer. Switch on the hard disk, wait about 10 seconds for it to come

up to speed, and then restart the computer."

 

From the Macintosh User's Guide for desktop Macs, page 216:

 

"IMPORTANT: Always turn on any external SCSI devices connected to your

Macintosh before turning on the computer itself. Otherwise, your

computer cannot recognize the SCSI devices."

 

___________________________

 

 

 

From: Randy Shackelford

 

015- Can I leave SCSI devices I'm not using OFF when I

turn ON my GS?

 

If it were not okay, I would have fried plenty of hardware. I do

this all the time. I have seen no problems with having some devices off.

As I have mentioned, I keep my magneto optical off most of the time;

and, my buddy who uses my 700 now has a flatbed scanner and leaves it

off most of the time. Both work fine.

 

____________________________

 

 

 

From: Daniel L. Miller

 

Related FAQs Resources: R008SCSITUT.TXT (text)

 

016- Is there a generic SCSI tutorial available for downloading?

 

Yes. Bus signals, commands, etc. for the Small Computer Serial

Interface are described in the text resource file R008SCSITUT.TXT .

 

____________________________

 

 

 

017- What is the correct time-out setting for a Focus hard drive?

 

From: Rubywand

 

Supposedly, the purpose of having the Focus spin down and stop

after 2, 10, or whatever minutes of idleness is to prevent over-heating

and unnecessary wear. After a few days of trying various TO settings, I

set my "Time Out" to "Never" and have had no problems with over-heating

or crashes even after many all-day sessions.

 

----------------------------

 

 

Related FAQs Resources: R009HSSTMOD.GIF (GIF pic)

 

018- How do I modify my Apple Hi-Speed SCSI card to supply

Termination Power?

 

The Apple High Speed SCSI Termination Power modification consists

of adding a diode. It is shown in resource file R009HSSTMOD.GIF from

Harold Hislop and Dan Brown.

 

The pic shows a simple sketch of the back of the Apple High Speed SCSI

card near connectors 26-33. The directions say that you connect a 1N914

diode between two points:

 

The anode (non-banded end) of the diode goes to the *top* of L1. The

cathode (banded/striped end) of the diode goes to the >bottom< of RP2

 

The pic shows the *top* of L1 to be a solder pad (just a solder pad with

no trace showing) a little ways up from a point between connectors 32

and 33.

 

The >bottom< of RP2 is just a bit up and to the left of the *top* of L1.

It is the lowest of several points (the pic shows 8) arranged in a

vertical column and should have a trace going off to the left.

 

____________________________

 

 

 

From: Scott G

 

019- Can I get a Focus drive bigger than a couple hundred MB?

 

Get a 40MB Focus Hard Card from Alltech. Get an 800MB IDE 2.5"

Quantum GO-drive from Computer Shopper sources for pennies. Replace the

original drive on the Focus Hard Card with the big one (VERY easy and

self-explanatory, just use a screw driver). Low level format,

partition, and high level format. That's it!

 

___________________________

 

 

 

From: Gary Black

 

020- On my ROM-03 GS the hard disk is connected to a CMS SCSI card.

How do I install System 6.0.1?

 

It turns out that the SCSI drivers that come on the Sys 6.0.1

Install Disk downloaded from ftp.apple.com are incompatible with CMS ver

3.0 (and probably earlier) SCSI cards.

 

What I did was to replace scsi.manager and scsihd.driver in the

System 6.0.1 Install disk SYSTEM/DRIVERS folder with scsi.manager,

scsihd.driver, AND CMS.driver from the CMS Utility disk.

 

With the replacement scsi drivers installed, the Install disk

recognizes the hard drive and installation went smoothly from that

point. (The CMS files are dated 1989 and 1990, so they are a bit older

than the 6.01 files, which are dated 1993. But, they work!)

 

____________________________

 

 

 

From: Scott G

 

021- How is DMA set for SCSI cards with 8MB RAM cards on the GS?

 

DMA needs to be turned off with the Apple HS SCSI card or the

RamFAST revision C card. It does not need to be turned off with the

RamFAST revision D card (differentiated by being half sized). All

Sequential Systems RamFAST cards are revision D as are late model CV

Tech cards. It is the RamFAST revision D that is designed to DMA into

any RAM card, even 8MB models. It was made around the time of the CV RAM

8MB model that turned into Sequential's RAM GS Plus, but functions just

as well with the Sirius card.

 

 

____________________________

 

 

 

From: Louis Cornelio

 

022- My 20MB Focus bombs and there's some goo on the card. A fix?

 

The goo is leaking from the drive due to a failed seal which seems

to plague some of the older Conner drive modules. The fix is to check

with the seller of the drive for a replacement. At Alltech, a good Apple

II person to contact is Tony Diaz.