Changes
Spelling and grammar
'''Amstrad''' made two different [[disk drives]] for the Amstrad/Schneider CPC range:
* DDI-1 - : a set, consisting of the real DDI-1 (= Disk Drive Interface) and a FD-1 3" disk drive, as well as the CP/M 2.2 license and disk.
This set was for the CPC464, which doesndidn't have the disk controller a built-indisk controller.
* FD-1 - : a 3" disk drive as secondary disk drive unit for the CPC664, CPC6128 and CPC464 with DDI-1
The cable decided which drive became A: and which one became B: :
* On the CPC664 and CPC6128 computers, DRIVE SELECT 0 was not wired externallyconnected on the external connector, so the drive could only become drive B: on these systems.* For the DDI-1, DRIVE SELECT 0 was only wired to the outmost outermost connector of the attached cable, while the inner connector was wired to DRIVE SELECT 1 only, thus the drive at the cable's end always became A: while the other one became drive B: accordingly.
Note that the drive also powered the DDI-1 interface when used together with it: . Certain pins documented as N/C in the CPC664/CPC6128 manual in fact carry +5V from the drive to the controller.The main benefit of reason for this was, that you couldn't connect a standard drive with a more common format (5¼" in the beginning, 3½" later and today) and thus cheaper disks as drive A: without modifications, as the DDI-1 wonwouldn't work without the power fed from the FD-1.
== Pictures ==