VM31 Firmware Versions
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xxx.001 
- first version

xxx.002
- autoranging improved, amplitude criterion (peak+ - peak-)/2 instead of peak+, better stability at low frequencies
- in range a: 0.2-1500Hz two subsequent measurements after autoranging suppressed, avoids invalid values

xxx.003
- safer changeover to USB power
- error in calibration menu removed

xxx.004
- hand-arm meassuring time (red timer) changed to 1 min

xxx.005
- RMS and peak values are not displayed after gain change (autoranging)
- minor hardware changes avoid occasional high current drain at start

xxx.006
- data logger function added
- error in answer to #S command fixed
- pressing arrow-right key skips the wait timer
- occasional reboot at 00:00 fixed

xxx.008
- cosmetic repairs in OEM versions

xxx.009
- crest factor measurement for whole-body 
- error in VDV calculation fixed
- improved battery indication

xxx.010
- changes in bootloader

xxx.011
- crest factor blocked in all modes except whole-body (bug fix)

xxx.012
- Display of future hardware versions on start screen

xxx.013
- error in log data export fixed

xxx.014
- SD card access improved (bugs and CRC)
- USB locked in FFT mode (may crash)
- saving during wait time blocked
- no wait time after return from menus
- power management in menu changed (always battery)
- sensitivity adjustment menu locked for TEDS sensors 

xxx.015
- occasional gain errors fixed

xxx.016
- in general vibration mode (acc./vel./dis.) display in large numbers selectable

xxx.017
- <EOT> symbol attached to USB acknowledge strings ("/a" and "/n") to avoid occasional freezing of Excel macro
- display in large numbers if only 1 uniaxial sensor connected to X
- saving function for crest factor blocked
- at TEDS sensitivities > 5 mV/ms^2 measurement with 3 digits after decimal point for aacceleration, 2 for velocity and 1 for displacement

xxx.018
- acc./vel./displ. measurements can be saved even if channels are overloaded (blocked for H/A and W/B)

xxx.019
- support for sensors with TEDS memory DS2431 
- frequency weighting Wp to ISO/TR 18570

xxx.020
- line end character in measurement data changed, solves problem with Excel macro file

xxx.021
- bug fix in automatic gain function, avoids glitches in interval RMS

xxx.022
- issues in data loggr fixed