19 Mar
2014
19 Mar
'14
10:22 a.m.
The RQDX2 controller (MFM and floppy) received the scatter/gather list as
part of the MSCP command - thus offloading the scattering and gathering to
the device.
On 3/19/14, 11:00 , "cctech-request at classiccmp.org"
<cctech-request at classiccmp.org> wrote:
On Tue, Mar 18, 2014 at 9:11 AM, Ethan Dicks
<ethan.dicks at gmail.com>
wrote:
That is essentially it. Between maxxing out at 4GB of RAM and how
slow the KD32 was, ISTR they didn't last long after the MicroVAX
II/VAXstation II came out a few years later.
(We all know you mean 4MB, not 4GB).
http://ifctfvax.harhan.org/Quasijarus/vaxhw/overview.html
Q22-bus MicroVAXen
KA610 aka KD32 was the first Q22-bus MicroVAX made. It is also the
worst VAX ever made. This is because it violates the two-layer bus
structure requirement (see above). KA610 aka KD32 is the only Q22-bus
MicroVAX on which there is no bus adapter or any other kind of nexus
standing between the CPU and the Q22-bus devices. KA610 aka KD32 uses
the Q22-bus as its VAX main bus and Q22-bus memory as main memory.
Among other horrible things, this means that the main memory is
limited to 4 MB and that no scatter-gather DMA is possible.