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Diffstat (limited to 'klippy/extras/bulk_sensor.py')
| -rw-r--r-- | klippy/extras/bulk_sensor.py | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/klippy/extras/bulk_sensor.py b/klippy/extras/bulk_sensor.py index a8497afc..23c98523 100644 --- a/klippy/extras/bulk_sensor.py +++ b/klippy/extras/bulk_sensor.py @@ -5,6 +5,18 @@ # This file may be distributed under the terms of the GNU GPLv3 license. import threading +# This "bulk sensor" module facilitates the processing of sensor chip +# measurements that do not require the host to respond with low +# latency. This module helps collect these measurements into batches +# that are then processed periodically by the host code (as specified +# by BatchBulkHelper.batch_interval). It supports the collection of +# thousands of sensor measurements per second. +# +# Processing measurements in batches reduces load on the mcu, reduces +# bandwidth to/from the mcu, and reduces load on the host. It also +# makes it easier to export the raw measurements via the webhooks +# system (aka API Server). + BATCH_INTERVAL = 0.500 # Helper to process accumulated messages in periodic batches @@ -119,6 +131,25 @@ class BulkDataQueue: def clear_samples(self): self.pull_samples() + +###################################################################### +# Clock synchronization +###################################################################### + +# It is common for sensors to produce measurements at a fixed +# frequency. If the mcu can reliably obtain all of these +# measurements, then the code here can calculate a precision timestamp +# for them. That is, it can determine the actual sensor measurement +# frequency, the time of the first measurement, and thus a precise +# time for all measurements. +# +# This system works by having the mcu periodically report a precision +# timestamp along with the total number of measurements the sensor has +# taken as of that time. In brief, knowing the total number of +# measurements taken over an extended period provides an accurate +# estimate of measurement frequency, which can then also be utilized +# to determine the time of the first measurement. + # Helper class for chip clock synchronization via linear regression class ClockSyncRegression: def __init__(self, mcu, chip_clock_smooth, decay = 1. / 20.): |