LVDT Measurement (Module L*)68C3 Operations Manual North Atlantic Industries, Inc. 12/19/2014Rev: 2014-12-19-0947 www.naii.com Page 211 of 330Bandwidth (BW)The bandwidth (BW) for each channel is individually programmable (when Bandwidth Select Register is set for“manual” mode). When operating in “manual mode” (please see/note Bandwidth Selection register description),write desired BW as unsigned integer, between 6 and 1280 (in 2 Hz increments), to associated channel register.All values greater than 1280 will be processed as 1280Hz. All values less than 6 will be processed as 6 Hz.Example: BW of 40 Hz = 028h.When the bandwidth select register is set for “automatic mode”, the automaticbandwidth (as calculated and set by the card algorithm) can be read.Bandwidth SelectBW Select register sets the “Automatic” or “Manual” Bandwidth control. This register is bitmapped per channel;(i.e. D0 = CH1, D1 = CH2, etc.). “1” indicates user wants automatic bandwidth. “0” indicates user wants manualcontrol.The Automatic BW feature, when enabled, reads the input reference frequency and automatically adjusts the BWto approximately 1/10 of the carrier frequency. This Auto BW range will be a minimum of 10 Hz with a maximumof 100 Hz.When in “Manual BW” mode, the user can enter the BW between a range of 6 Hz and 1280 Hz, in 2 Hzincrements.REGISTER D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 FUNCTIONBANDWIDTH SELECT X X X X X X X X X X X X Ch4 Ch3 Ch2 Ch1 D=DATA BITActive ChannelsType: binary wordRange: N/ARead/Write: R/WInitialized Value: N/ASet the bit corresponding to each channel to be monitored during BIT testing in the Active Channel register. Set bit to “1” foractive channels and clear bit to “0” for those not used. NOTE: Omitting this step will produce false alarms, because unusedchannels will set faults.REGISTER D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 FUNCTIONACTIVE CHANNEL X X X X X X X X X X X X Ch4 Ch3 Ch2 Ch1 CHANNEL ENABLE BITLatch (Track/Hold)Type: 16-bit unsigned integerRange: 0 or 2Read/Write: RInitialized Value: 0Writing the integer 2 to the Latch register will cause all the channels to be latched. Reading a particular channelwill disengage the latch for that channel. Writing a 0 to this register will disengage latch on all channels.REGISTER D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 FUNCTIONTRACK/HOLD D D D D D D D D D D D D Ch4 Ch3 Ch2 Ch1 D=DATA BITTest (D2) VerifyCard will write 55h at Test (D2) Verification register when (D2) is enabled, approximately every one second. Usercan clear to 00h and then read again, after approximately one second, to verify that background bit testing isactivated.
