Jumper Configurations
Table A-1
Jumper Descriptions (continued).
JUMPER #
DESCRIPTION
W39
This jumper controls the use of the printer
port signal ERROR*. Removing W39 allows
for the use of ERROR* by the printer. In-
stalling W39 allows the STD bus interrupt
request signal (INTRQ*), inverted once, to
be read as a status bit at the printer port
signal
ERROR*.
This
assumes
that
ERROR* is not being used at the printer.
STD
DOS
uses ERROR*
for
reading
INTRQ*, so the ZT 90039 printer cable does
not drive this signal to the printer. Factory
default installs W39 for STD DOS use and
removes it for STD ROM systems. Refer to
Chapter 9 regarding the printer interface for
further detail.
W39
Function
IN †
INTRQ* STD bus pin read through
printer ERROR* input
OUT ††
ERROR* used at the printer
A-29