12 Aug
2004
12 Aug
'04
10:33 a.m.
From: "Fred Cisin"
<cisin(a)xenosoft.com>
On Thu, 12 Aug 2004, Dwight K. Elvey wrote:
True, but it does require the hardware to be setup for it.
I have a Forth processor ( NC4000 ) that I talk directly
to the controller chip without DMA. Newer processors are
faster but may have latency issues. Using a dedicated uP
or some FPLA is the right way to handle it.
Of course the problem is multiplies when you have no controller
chip and you are talking about raw bit streamed data.
It was mentioned earlier that for logging bit stream data,
the gaps my have trash in them that causes loss of sync. This
should also be handled in the specification.
Dwight
Hi Jules
Here is what I've found. It is a disk drive emulator.
Unless a PC is DMA driven, bit banging a floppy is not practical.
Disk I/O without DMA is not practical. But it IS possible.
Consider the PCJr and Tandy 1000, both of which do disk I/O
without DMA on 4.77MHz? machines.