SD Card disk drive for C-64?

drlegendre . drlegendre at
Sat Jan 23 19:15:26 CST 2016

" I am saying don't make a permanent hardware change to a 1541 that
does not have the switches unless you really want it to be permanent
because there is a software method of assigning drives that is good enough
most of the time.  BUT if you must make it permanent and you don't have the
external switches, consider adding some form of external switch so you
don't ever have to open the case again to put it back to the default."

Well then, we're having a major agreement. ;-)

The device ID switch is the ultimate fix for Commodore drives, and I'm
really not sure why CBM didn't incorporate one into the design - at least
from the 1540 on upwards. Can't have cost much to add a discretely located
access hole (or a knock-out) in the case, along with a 2-place DIP switch
for controlling device ID.

Grumble grumble..

On Sat, Jan 23, 2016 at 6:33 PM, Jim Brain <brain at> wrote:

> On 1/23/2016 6:28 PM, Eric Christopherson wrote:
>> On Sat, Jan 23, 2016, Jim Brain wrote:
>>> On 1/23/2016 2:18 PM, drlegendre . wrote:
>>>> First off, my bad - I thought the OP was wanting to change the device ID
>>>> (which is not the drive number, btw**) on a genuine 1541. I'd have no
>>>> idea
>>>> how it's done with one of the SD-based drive emulators.
>>> Google is still a friend:
>>> There are no external switches on some of these drives.
>>> But, the BASIC commands used to switch device numbers on the 1541 also
>>> work
>>> on these units, and putting an extra char at the end of the command will
>>> make the changes permanent, as I recall.
>>> Jim
>> Jim, don't you sell a device that's useful for temporarily switching off
>> specific drives so the device numbers can be changed more easily?
>> QuadPortIEC, but you can also just switch the ATN line on the cable.
> Disabling the ATN (Attention) line means the drive will not respond to any
> commands.
> Jim
> --
> Jim Brain
> brain at

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