[Coco] CoCo IDE interface

[Dave Philipsen]

Actually, it wasn't an arbitrary point.  It was at the AT bus.  Most of 
the IDE (Integrated Drive Electronics) signals are the same as the 
signal names on the AT bus.  The IDE drive was just an integration of 
the hard drive controller (which was previously a board that plugged 
into the bus of a PC) to the hard drive itself. The idea in itself was 
not a bad idea.  Instead of buying a single HD controller card and 
hoping it would work with any manufacturer's HD the idea was that each 
manufacturer would design the controller for its own particular HD and 
integrate it as part of the HD.  Then it would be a simple matter of 
attaching the drive to what amounts to an extension of the AT bus. The 
IDE interface in one form or another existed as the defacto standard for 
many years and, indeed, it did help to standardize and simplify the 
connection of a hard drive to a PC.  As Stephen pointed out the SCSI 
interface has always been a superior albeit more expensive method.

That being said, I doubt that a Color Computer running at less than 2 
MHz would be able to realize the performance gains that a SCSI offers 
over an IDE to any reasonable extent.  The bus speed of an IDE interface 
is faster than the clock speed of the 6809 in the CoCo.

Dave Philipsen

On 7/9/2015 2:43 PM, Stephen H. Fischer wrote:
> IDE = Idiot Designed Equipment.
>
> Some engineer took a hacksaw to an arbitrary point in the computer to hard drive electronics and said that was a good place to have an interface.
>
> As opposed to the SCSI interface it could be built a few cents cheaper so the computer world went with it.
>
> Now if you look at hard disks they are SCSI in the end with a conversion to / from the SATA interface. The drive commands are SCSI commands in the end. (CoCo Hard drives YMMV)
>
> I purchased two Glendale boards to support their effort, I just saw the box containing them the other day.
>
> SHF
>
> ----- Original Message -----
> From: "George Ramsower" <georgera at gvtc.com>
> To: <coco at maltedmedia.com>
> Sent: Thursday, July 09, 2015 12:24 PM
> Subject: Re: [Coco] CoCo IDE interface
>
>
>>   What is an IDE interface? I assume it's for an IDE hard disk but you
>> never know!
>> George R
>>
>>
>> On 7/9/2015 1:59 PM, camillus wrote:
>>> Hi, john,
>>>
>>> I purchased a bunch of those pcb's from glenside, the boards are "untested". I did not get on to it to test them all, but if you willing to test them yourself ( testing means that every link needs to be probed with ohm meter ), I can do $5 a board(that includes all the chips and the pcb, with the exception of the 40 pin cartridge connectors) + shipping.
>>>
>>> Let me know if interested. I think the schematics are in the archive somewhere, need to look it up. If you find it then please send me a copy...
>>>
>>> Thanks
>>>
>>> Camilus blockx
>>>
>>> Sent from Mailbird [http://www.getmailbird.com/?utm_source=Mailbird&utm_medium=email&utm_campaign=sent-from-mailbird]
>>> On 7/8/2015 4:57:51 PM, John B <trymyz at gmail.com> wrote:
>>> Where is a good place to purchase an IDE interface/adapter for the CoCo? I
>>> did a little research and it appears that Glenside Computer Club did make a
>>> board at one time. Do they still make it? If not, are there board files
>>> and/or a schematic so I can make my own?
>>>
>>> Thanks
>>>
>>> John
>