Re: Computer Choice

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "jcc3inc" <jccinc@o...> wrote:

> Gentlemen:
> I am considering getting a newer computer to replace my 133 MHz

unit.

> I will use it for either a DOS based controller or a MachII which
> needs WinXP, I understand. A used unit around 500 MHz might be OK!
> What kind of connectors do I need for the parallel port cards? Are
> ISA slots in the later models? Will I have any problems in using

PCI

> cards if I stick to DOS programs? And how much should I expect to
> pay? My present unit was $35 two years ago.
> I get by with Windows but certainly am no expert!
> Thanks,
> Jack C.

Newer machines often have a motherboard parallelport that is at the
standard DOS LPT1 address of 0378hex and will work with all of the
DOS based CNC programs. You may find that the output from the port
is weak (3.3V vs 5V) compared to the older machines and you will need
to buffer it using either a 74LS451 Octal Buffer or purchase one of
the buffered interface port cards available.

The interesting part comes when/if you add the second parallel port.
The system when it boots up will not see the card as a standard
port. The card will need a special DOS level driver that loads in
the Config.sys file on bootup to redirect the real card address over
to the fake 0278hex address for LPT2.

Under MACH2 in Win2000 or XP you can set it to find the second
parallel port at any hex address. If your card shows in the Windows
Device info to have two hex addresses, then just use the beginning
address of the first one.

Sometimes overlooked is the fact that WIN2000 is a stable operating
system for MACH and it brings less baggage to the party than XP. I
am running all of my machines on WIN2000 including my Controller on
MACH2 and they are all networked and have internet access. I have
never had a hint of a problem running any of the Windows programs I
use or MACH1 or 2. Tests from several MACH users indicate that
WIN2000 runs better on a slower computer than XP. At work we run 64
major servers that can't afford to be down and all of them are
running WIN2000 Advanced Server.