Released 1985: Late in 1985, Commodore released to the European market a new version of the C128 with a redesigned chassis resembling the Amiga 1000. It was named the Commodore 128D, this new model features a plastic chassis with a carrying handle on the side, incorporates a 1571 disk drive into the main chassis, replaces the built-in keyboard with a detachable one, and adds a cooling fan. The keyboard features two folding legs for changing the typing angle.
According to Bil Herd, head of the Hardware Team (a.k.a. the “C128 Animals”), the C128D was ready for production at the same time as the regular version. Working to release two models at the same time had increased the risk for on-time delivery and was apparent in that the main PCB has large holes in critical sections to support the C128D case and the normal case concurrently.
In the latter part of 1986, Commodore released a version of the C128D in North America and parts of Europe referred to as the C128DCR, CR meaning “cost-reduced”. The DCR model features a stamped-steel chassis in place of the plastic version of the C128D (with no carrying handle), a modular switched-mode power supply similar to that of the C128D, retaining that model’s detachable keyboard and internal 1571 floppy drive. A number of components on the mainboard were consolidated to reduce production costs,
A significant improvement introduced with the DCR model was the replacement of the 8563 video display controller (VDC) with the more technically advanced 8568 VDC and equipping it with 64 KB of video RAM (all C128 models can easily be upgraded to 64 KB video RAM). The increase in video RAM made it possible, among other things, to maintain multiple text screens in support of a true windowing system, or generate higher-resolution graphics with a more flexible color palette.
My C128D, repair and upgrade:
Was lucky enough to get my hands on a working unit in its original box. It had some instability wit the disk drive LED due to “loose” soldering on the small LED card in the front, a new solder took care of that. Also upgraded the VDC chip video RAM to 64 KB instead of the original 16 KB, 64 KB video RAM came originally with the later C128D-CR version (cost reduced).