The Input Mask Instruction, Im - HP 7470A Interfacing And Programming Manual

EXPLANATIONNo parameters are used; a numeric parameter will
cause error 2 and the instruction will not execute.
An IN command is the equivalent of switching the plotter off and then
on again (except that conditions set by escape code sequences are not
changed in an RS-232-Cenvironment). The initialize command sets the
plotter to the same conditions as the default command and sets these
additional conditions.
0 The pen is raised.
0 The scaling points P1 and P2 are set to the points P1 = 250,279 and
P2 = 10 250 , 7479.
0 All HP—GL errors are cleared. Bit position 3 of the output status byte
is set to true(1) indicating the plotter has been initialized. (This bit is
cleared by OS.)
0 The setting of the Us/A4 switch (for paper size) is read, thus
establishing the limits within which the pen can move (mechanical
hard clip limits).
The Input Mask Instruction, IM
The input mask instruction, IM, controls the conditions
under which HP—GL error status is reported, the conditions that can
cause an HP-IB service request message, and the conditions that can
cause a positive response to an HP-IB parallel poll.
E With all three interfaceconfigurations(HP-IB,HP-IL,and RS­
232—C), this instruction can be used to change the conditions under
which HP—GL error status is reported. In an HP-IB system only, the
instruction is used to enable the plotter to send a service request
message when specified bits of the status byte are set, and/ or enable a
positive response to a parallel poll under the conditions specified.
IM E—maskvalue (,S-mask value (,P—maskvalue))
(terminator)
or
IM (terminator)
EXPLANATION In both the RS-232-C and HP—ILconfigurations, the S­
and P—masksare of no use and are ignored if present. The E—maskis
used by all three configurations.
The E—maskvalue specified is the sum of any combination.of the bit
values shown in the following table. When an HP-GL error occurs, the
bit in the E—mask corresponding to the error number as shown below is
tested to determine if the error bit (bit 5) of the status byte is to be set
and the front panel ERROR LED is to be turned on. If a bit is not set,
there is no way to ever determine if that error occurred.
1-12 GETTING STARTED