I'm using MCC 128 and MCC 172 for data acquisition and noticed frequency is not exact.
My application is continuous acquisition and split data at every hour reached, timestamps of these file is increasing constantly like
00:00:00.data
01:00:00.data
02:00:01.data
03:00:01.data
04:00:02.data...
, every file has exactly same size because it just appends data from "a_in_scan_read(frequency, timeout)" 3600 times to binary.
This application running on 2048 Hz, and I know MCC128 has cannot achieve 2048 Hz (it shows 2047.8... Hz from a_in_scan_actual_rate()), but in MCC172 shows 2048 Hz but it drift about 0.02~0.07 seconds per hour. Of course data is continuous.
These RPis has GPS source, it syncs time from GPS every minute.
Question
skycraper3
Hello,
I'm using MCC 128 and MCC 172 for data acquisition and noticed frequency is not exact.
My application is continuous acquisition and split data at every hour reached, timestamps of these file is increasing constantly like
00:00:00.data
01:00:00.data
02:00:01.data
03:00:01.data
04:00:02.data...
, every file has exactly same size because it just appends data from "a_in_scan_read(frequency, timeout)" 3600 times to binary.
This application running on 2048 Hz, and I know MCC128 has cannot achieve 2048 Hz (it shows 2047.8... Hz from a_in_scan_actual_rate()), but in MCC172 shows 2048 Hz but it drift about 0.02~0.07 seconds per hour. Of course data is continuous.
These RPis has GPS source, it syncs time from GPS every minute.
Is it normal or have to handle in code?
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