Need help setting up a CMS hard drive for an Apple //e

2 replies [Last post]
A2forever's picture
Joined: Dec 20 2003
Posts: 226

Need help setting up a CMS Hard drive for a apple //e. The CMS card has dip switches on it and I am not exactly sure what they do.
Plus there are dip switches on the back of the hard drive.

Hopefully you guys will be able to help Shock)

Thanks again.



Long Live The Apple ][

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speedyG's picture
Joined: Nov 16 2011
Posts: 2426
Re: Need help setting up a CMS hard drive for an Apple //e

which controller is used --- cms made at least 4 different controllers ! so which one are we talking about ( model ) ?
the different harddrive companies equipped their drives with different switches - so first of all: what type of drive ( model-no. ) and which company ??? unless this is answered the correct setup can´t be given....
in several cases for example it is important to decide if the drive has internal termination set and that affects the setup of the switches on the card too... and if more dives are connected the models / companies of ALL drives need to be specified.... or is a external terminator used ?

additional edit after 2 days without answer...:

after all it seems this thread was dropped before it starts , because there is no reply from the initiator.....

nevertheless .... probably the question rises up again - so a general reply :

at the drives each drive has to be set to a unique ID-No. - thats a kind of "adress" for each drive and within an SCSI-chain - it is not permitted to the devices to share the same adress....

the devices have somewhere close to the cableconnector some pins and usually some of the pinpairs are labeled
ID0, ID1 and ID2
and with a combination of the jumpers you might be able to set an ID between 0 and 7 resulting from the addition of the ID-pins at the drive which represent the binary value of the settings -
The ID0 is Bit1, ID1 is Bit2 and ID2 is Bit4
- so for example ID1 and ID2 is the addition of 2 + 4 = and the result will be Adress ID 6
or as alternate example ID0 and ID1 closed with jumpers will assume to Bit1 and Bit2 and the summary will be 1 + 2 = and the drive ID will be 3.
No jumper set will assume the driveID to be 0...

another Jumper at the drive will probably be labeled with "term" and only the manual will expalin if the refers to the Jumersetting if the closed Jumper means the termination to done with an external Plug or if this means that the drive is terminated internal and if the drive is terminated internal this might probably only work if the resistorblocks are populated on the drive....
in some cases the resistors a 3 SIL-Packages and
in other cases the resistors are in DIL-ceramic-cases...

if the resistors are in SIL-case it is important to make sure that pin1 of the case is in pin1 of the carrier, because that is the common internal connection of the resistors in the SIL-case.

If the "internal resistors" are not present on the drive the setting of the PINs of the drive ID-Block to internal termination will not work.

The similar point must be set at the Interface card in most cases too ...

So in case that this question is repeated again - it is vitaly important to also list up all devices and the interface otherwise you might get a wrong answer.... and it is also a advice to add pictures of the backpart of the PCB from the drives to determine if the termination-resistors are present or not... this might lead up to the decession which drive should be at the and of the daisychain of the SCSI-bus.


In early days I had a lot of money but no time - now I have no money but a lot of time....
the second part includes less friends but a lot more joy on life....

Joined: Dec 20 2003
Posts: 361
Re: Need help setting up a CMS hard drive for an Apple //e

There's a bit of info on CMS SCSI cards ion the Apple II FAQ