HP 6002A/HP 1000
Buffering
The buffering option for the 6002A EQT should
be
turned off
until the device
has
been tested for valid operation.
:SYEQ,10,UN
will set the 6002A EQT to the unbuffered mode.
Although the time-out for the 6002A EQT must
be
a com-
promise for
all
devices
on
the HP-IB, the 6002A time-out can
be
as
short
as
one second. The time-out
is
an
errorcondition
for this device.
The 6002A either listens
and
accepts programming informa-
tion, or
an
error condition exists (the 6002A hardware is
inoperative). For this reason, it
is
usually satisfactory to allow
the operating system to handle time-out errors. (The device
configuration word defaults to this condition.) From File Man-
ager, a system request may be used to set the time-out
value:
:SYTO,10,100
will set the time-out
on
EQT 10 to one second.
Configuration
The 6002A
is
a device which will need special configuration
on HP-IB. Four ASCII characters are expected
by
the power
supply. These characters do not include
an
end-of-record
terminator. (The carriage return (CR), linefeed (LF) ter-
minator will confuse the 6002A.) When
an
ASCII write
re-
quest
(a
formatted "WRITE" from FORTRAN, for example)
is
performed
in
the
HP
1000, a CRLF is automatically sent as
the record terminator.
By
inserting the underline character
C'_
")
at
the end of each output record, the end-of-record
terminators may
be
suppressed. This method must
be
used
each time a write request
is
made to the 6002A. See the
example FORTRAN program
in
figure 9-4 for more details.
SRQ is not applicable to the 6002A. The default SRQ config-
uration
is
satisfactory.
DMA
is
not usually allocated for the 6002A so the device
configuration word should
be
checked to see that a DMA
channel
is
not inadvertantly allocated.
The
I,J,
and P bits of the configuration word are not applica-
ble to the 6002A, and may
be
left at their default values.
9-2
From File Manager,
:CN,17,25E,17000E
"
will assure that
LU
17 (the 6002A)
is
configured correctly.
Remote
The
6002A
need
not be
configured
into remote for
programming.
Programming
Because record terminators
are
not accepted, File Manager
should not
be
used to check out the power supply.
The HP-IB option (001)
is
basically adigital-to-analog conver-
ter (DAC) that voltage-programs the power supply's constant
voltage (CV) or constant current (CC) output
in
the high
or
low range. The DAC automatically provides a voltage-
programming output to the power supply
as
soon
as
four
digits are received. This output
is
retained until the next four
digits are received. The DAC
is
programmed
by
the mag- ,---../'
nitude digits
in
BCD
in
such a way that 000 equal 00.0% of
full range, 500 equals 50.0% of full range, and 999 equals
99.9% of full range.
The magnitude of the constant voltage (CV) or constant
current (CC) output of the power supply
is
programmed by a
data word comprised of four ASCII characters (digits) re-
ceived
in
the order shown by figure 9-2. The first digit
specifies range and the next three digits specify the desired
magnitude (percentage of full scale).
01
I
Range
1 or 2
02 03
04
~~-------'r~------_/
Magnitude
000-999
Figure 9-2. 6002A Data Word Format
