11 Feb
2006
11 Feb
'06
2:45 p.m.
On 2/11/2006 at 2:23 PM Fred Cisin wrote:
When the XT came out, IBM did not want people to plug
other boards in
there. They also had a horrendous surplus of some boards, such as the
Asynch (RS232 & 20mA), due to the popularity of "multifunction" boards.
So the XT was sold with a "FREE" Asynch board already installed in slot 8.
Under "puzzles for the ages", one might also wonder what the IBM was
thinking when they added the 20ma current loop circuitry to the board. Did
they really think that folks were going to use them to drive an ASR 33? Or
that RS232-to-current loop adapters were hard to obtain?
Cheers,
Chuck