[Coco] Access to Double Sided Disks with standard Floppy

[Barry Nelson]

Yes, it can also be done by connecting two diodes so that when another drive select line is activated, it selects both the second side of the disk and also selects the drive select line the drive normally responds to.

Using ASCII art to draw a schematic

From controller, 0=drive select for drive 0, 1=drive select for drive 1 or other number, S=side select
0    1    S
|    |    |
|->|-|-|<-|
|    |    |
To drive

Note that this circuit does sometimes confuse the drive controller software, so doing a dir is recommended before accessing the other side of the disk. Or use ADOS instead, as was previously mentioned.

On Apr 22, 2015, at 12:28 PM, coco-request at maltedmedia.com wrote:

> Date: Wed, 22 Apr 2015 09:16:00 -0400
> From: "Bruce W. Calkins" <brucewcalkins at charter.net>
> To: "CoCoList for Color Computer Enthusiasts" <coco at maltedmedia.com>
> Subject: Re: [Coco] Access to Double Sided Disks with standard Floppy
> 	Drives	onthe CoCo?
> Message-ID: <336904242A5A497C86B8E41A096CC939 at speedy>
> Content-Type: text/plain; format=flowed; charset="utf-8";
> 	reply-type=original
> 
> ----- Original Message ----- 
> From: "Steve Batson"
>> 
>> Anyone know of a program that lets you use the other side of a floppy as 
>> another CoCo Drive? I used to have custom Disk Basic ROM, but that's long 
>> gone when I sold that system. I have data on the other side of some of my 
>> disks and don't know how to get to it. These are NOT Flippy Disks so 
>> accessing them that way is not going to work.
> 
> =========================
> 
> My first CoCo disk drive was a double sided unit with a transister and some 
> wireing on the drive's drive select circut to map the second side as drive 
> 1.
> That was a long time ago and several disk setups so I doubt I can 
> reconstruct it.
> Bruce W.