HP 82479A Owner's Manual page 65

SECTION
STRIP CHART PROGRAM En
The strip chart program simulates the operation of an analog strip chart recorder by taking readings from
the HP 3421A Data Acquisition/Control Unit and producing a strip chart on the HP 2225B ThinkJet
Printer. The program supports up to nine traces, each with its own scale. Each scale has 100 divisions, and
is presented across the page. The time axis is presented down the page, so one set of readings is represented
on each line of the printout. The program gives you the option to store the readings in a data file. (To
avoid excessive power consumption, the file should reside in RAM.) The minimum components in a strip
chart system are an HP-71B Handheld Computer, an HP 82401 A HP-IL Interface, an HP 3421A Data
Acquisition/Control Unit, and an HP 2225B ThinkJet Printer. (If you are using some other printer
device, refer to appendix F, "Alternative Peripheral Options")
6.1 MEASUREMENT CHOICES
Each trace takes a measurement from the HP 3421 A using one of 20 available functions:
SIGNALS TEMPERATURE DIGITAL
DC Volts T,£,J,K,R,S Thermocouples Digital Bit
AC Volts 2252 Ohm Thermistor (2WQ) Digital Byte
4-20mA Current 2252 Ohm Thermistor (4WQ)
2-Wire Ohms 5000 Ohm Thermistor (2WQ)
4-Wire Ohms 5000 Ohm Thermistor (4WQ)
Frequency European RTD (x=.00385) (2wQ)
European RTD (x=.00385) (4WQ)
Most functions may call a user-written conversion program which may be used do perform additional
processing on each measurement, such as a unit conversion.
As an alternative to these functions, a trace may call a user-written custom program. This allows the
user to include a measurement from a sensor or instrument that is not directly supported by the STFIF
program.
6.2 STRIP CHART OPERATION
The = TFIF program is driven by a setup, which contains a list of the specifications for each trace. If you
want to use a setup repeatedly, you should store it in a setup file before exiting the program. A strip
chart setup consists of the following information:
¢ The number of traces.
e The sensor and channel number to be used for each trace.
e The scale to be used (minimum and maximum bounds) for each trace.
e The conversion subprogram to be called (optional) for each trace.