Synchronizing Acquisitions 42Keysight InfiniiVision 4000 X-Series Oscilloscopes Programmer's Guide 1603# can reflect states for other oscilloscope properties, for# example, if the oscilloscope is armed, thus it can produce# values other than 0 (stopped) or 8 (running).## To handle that, the result of :OPERation:Condition? is bitwise# ANDed (& in Python) with an 8. This is called "unmasking".## Here, the "unmasking" is done in the script. On the other# hand, it is possible to "mask" which bits get passed to the# summary bit to the next register below on the instrument# itself. However, this method it typically only used when# working with the Status Byte, and not used here.## - Why 8 = running = not done?## The Run bit is the 4th bit of the Operation Status Condition# (and Event) Registers.## The registers are binary and start counting at zero, thus the# 4th bit is bit number 3, and 2^3 = 8, and thus it returns an# 8 for high and a 0 for low.## - Why the CONDITION and NOT the EVENT register?## The Condition register reflects the CURRENT state, while the# EVENT register reflects the first event that occurred since it# was cleared or read (as in: has it EVER happened?), thus the# CONDITION register is used.## Note that with this method using :SINGle, for InfiniiVision# X-Series oscilloscopes only, :SINGle itself forces the trigger# sweep mode into NORMal. This does not happen with the blocking# method, using :DIGitize, or on the InfiniiVision notXs.# ====================================================================def polling_method():MAX_TIME_TO_WAIT = SCOPE_ACQUISITION_TIME_OUT/float(1000)# Time in seconds to wait for the oscilloscope to arm, trigger,# and finish acquisition.## Note that this is NOT a property of the device interface,# KsInfiniiVisionX, but rather some constant in the script to be# used later with the Python module "time", and will be used with# time.clock().# Define "mask" bits.## Mask condition for Run state in the Operation Status Condition# (and Event) Register.## Refer to Programmer's Guide chapters on Status Reporting and# Synchronizing Acquisitions.RUN_BIT = 3# The run bit is the 4th bit (see next set of comments @# Completion Criteria).RUN_MASK = 1<# This basically means: 2^3 = 8, or rather, in Python 2**3
