BMU v19 Changes
 1) Added the ability for the Heartbeat signal to be used for multi-string systems.  Once the coordinator has been established, it will send the Heartbeat in the Application Command message to other strings.
 2) Added the feature to allow external thermal switch to trigger an input (C_Ext_Temp_Charge_Protection_Enable).  When the switch is above the thermal limit, BMU will derate the available charge current.
    a) The switch can be set as normally closed (provide signal when below temperature setpoint) or ON. Also the switch can be normally open (provide signal when above temperature setpoint) or OFF.
    b) The amount to derate can be set between 1 - 100%.
    c) A time limit can be set that will turn off the derate after the elapsed time has occurred.  Note: the derate will not trigger again until the thermal switch gets reset to normal condition.
 3) Added the feature for SOC threshold output.  This will trigger 1 output "on" when SOC is equal to and above OR equal to and below a configurable setpoint.
 4) Added delta Temperature monitoring setting and some options:
    a) C_cg_Temperature_Delta_per_Sec configuration parameter allows the degrees C change per second setting to be used (valid options 0 - 30 deg C / second).  If the value is 0, then option is turned off.
    b) If any temperature measured by the BMU is greater than or equal to the value for greater than or equal to C_cg_Temperature_Delta_Time in seconds, it will set FC166 latched disconnect fault.
    c) C_DTC_Thermal_Threshold_Active_IO_Mask configuration parameter will turn on an output if FC166 (described above) along with maximum temperature fault (FC 108) OR minimum voltage far below normal range (FC 113) are triggered.
       The output turns off automatically if the DTC's are no longer reporting.  This output is designed to warn of possible extreme thermal event or internal short circuit event in a battery cell.
 5) Service Tool 2.3.139 was updated to check new configuration parameters during firmware creation.
 6) Service Tool 2.3.139 works with v19 and below BMU firmware files.
 7) Service Tool 2.3.144 was updated to allow multiple output pins assigned to contactors during firmware creation.
 8) Service Tool 2.3.144 now will show the names of 2 input or output pins if the assigned pin values interfere.
 9) Service Tool 2.3.144 works with v19 and below BMU firmware files.

================================================================================================================================================================================================

BMU v18 Changes
 1) Fixed bug for a high number of cells and temperatures (>400 cell voltages) where the BMU would take longer than 5ms to process a frame.  The behavior happened 1 time per minute and was tied to background effective temperature calculations.
 2) Changed C_CAN_Cell_Voltage_Msg_Msec transmit times to reduce BMU processor overhead.  So BMU will send 2 messages at a time now, but call to the function much less.
 3) Changed repeated calculations that fell on even 1 second cycles to still occur at 1 second interval, but start offset either 10 or 20ms off 1 second increments.  This reduced the processor load especially for large systems like #1.
 4) Added delta Temperature monitoring setting and some options:
    a) C_cg_Temperature_Delta_per_Sec configuration parameter allows the degrees C change per second setting to be used (valid options 0 - 30 deg C / second).  If the value is 0, then option is turned off.
    b) If any temperature measured by the BMU is greater than or equal to the value, it will set FC166 latched disconnect fault.
    c) C_DTC_Thermal_Threshold_Active_IO_Mask configuration parameter will turn on an output if FC166 (described above) or maximum temperature fault (FC 108) are triggered.  The output turns off automatically if the DTC's are no longer reporting.
 5) Added new option to create a latched disconnect fault condition C_FC167_Enable_Latch if FC112 cell voltage far above normal range or FC113 cell voltage far below normal range.  FC112 and FC113 will auto-clear when voltage returns to normal range.
    This will prevent overcharge or over discharge bouncing effect if the voltage auto-clears and the load is still trying to charge/discharge.
 6) Removed FC149 fault code as it was configured not to be used in the default firmware.
 7) Service Tool 2.3.136 was updated to check new configuration parameters during firmware creation.
 8) Service Tool 2.3.136 works with v18.

================================================================================================================================================================================================

BMU v17 Changes
 1) Fixed bug when Auto-Ready was enabled and Wake line C_Manual_Power_Down_Enable was set to 1, system would not go into READY state.
 2) Added ability to activate selective contactors when C_Contactor_Control is set to 1. New valid options listed below:
    a) Negative only (not valid with Multi-String enabled)
    b) Positive only (not valid with Multi-String enabled)
    c) Positive with Precharge
    d) Positive and Negative (not valid with Multi-String enabled)
    e) Positive, Negative and Precharge
 3) Added more points [22 total now] to the SOC vs OCV lookup table (C_Table_data_OCVcg_to_SOCcg).  Table data not compatible with older versions.
 4) Changed impedance tables to use Temperature vs SOC instead of Temperature vs OCV.  This helped improved SOC accuracy.
 5) Updated SOC algorithm to improve accuracy.
 6) Updated SOC vs OCV and 4 impedance tables for 70 Ahr cell data.  This only affects ".sw" file as we have the default values already entered on the start ".bms" file.
 7) Added overcurrent protection as an option (C_Overcurrent_Protection_Enable).  Added new parameters to configure current options:
    a) C_Current_Limit_Cmd_Threshold when current is above this threshold, FC116 Charge or FC133 Discharge warning fault code will be active.
    b) C_Overcurrent_Factor when current is above this threshold, countdown will start see C_Overcurrent_Detection_Time.
    c) C_Overcurrent_Detection_Time is length of time current can be greater than C_Overcurrent_Factor before FC117 Charge or FC134 Discharge disconnect fault code will be set.
    d) C_Overcurrent_UL is maximum threshold that will set FC117 Charge or FC134 Discharge disconnect fault immediately.
    e) C_Overcurrent_LL is minimum amount of current allowed if Charge Limit or Discharge Limit go to 0.  This prevents the system from going into fault immediately if current goes 1 amp above or below threshold.
 8) Tmax and Tmin message (0x18FF03xx) now sent 100 msec intervals.
 9) Switched Pack Voltage message (0x18FF01xx data 04 and 05) will report 0 volts if BMU is idle and no valid voltage is sensed, otherwise reports sensed voltage or OOR number if BMU is in Ready state and the sensor goes out of range.
 10) Service Tool was updated to show only contactors that are configured on Pack Summary screen.
 11) Service Tool checks for proper configuration of contactor masks for v17.
 12) Service Tool checks for proper configuration of Overcurrent variables.

================================================================================================================================================================================================

BMU v16 Changes
 1) System configuration of maximum 512 cells, 208 temperatures and 52 LMU's.
 2) Changed multi-string available charge current (reported on CAN bus message 0x18FFE0##) to be lowest charge current available X number of active strings online.
 3) Added setting "C_App_Available_Disch_Curr" which affects available discharge current reporting.  Option 1 will do a sum of all available discharge currents, while option 2 behaves like available charge current.
 4) Changed charge/discharge reported available current for multi-string and single string to read 0 unless contactors are closed and current can flow.
 5) Changed setting "C_CAN_Cell_Voltage_Msg_Msec" to allow for 5 msec between each cell voltage message (settings are now 5, 10, 20 or 50 msec).  This allows for all cell voltages in a 512 cell system to be reported within 1 second.
 6) Updated SOC vs OCV and 4 impedance tables for 70 Ahr cell data.  This only affects ".sw" file as we have the default values already entered on the start ".bms" file.

================================================================================================================================================================================================

BMU v15 Changes
 1) Fixed bug where FC152 Pack Voltage Sensor OOR which is DERATE level caused a disconnect while operating.
 2) Added Auto-Ready functionality for systems without a main controller.
 3) Added I/O pins for tracking BMU state of DERATE or higher active (output), reset DTC (input) or Limp Mode (input).
 4) Reset will only remove non active latched DTC. Limp Mode will override most faults to allow the vehicle to move out of dangerous situation like stalled on train tracks.
 5) Added ability to display SOC with 3 output pins. Choice of binary signal (8 graduations) or fuel gauge (4 graduations).
 6) SOC output levels are configurable for when each transition happens.
 7) Added show SOC input for applications where the output should not be on full time, which could run down battery.
 8) Added output pin for when battery can accept charge (2 pins standard charge and high rate charge).
 9) High rate charge typically used from 0 - 93% (stop point is configurable), with standard charge active until full charge.
 
================================================================================================================================================================================================

BMU v14 Changes
1) Resolved External and Internal CAN Communication issues.
2) Resolved 508.0 C reporting due to improper initialization/error handling.
3) Resolved where External Contactor State was not initialized, now Unknown.
4) Resolved issue with TMax_ID and TMin_ID not reporting correctly.
5) Resolved initialization of SOC, Pack SOC, Temperature, and Voltage when LMU changes occur fault codes are not re-checked.
6) Resolved issue when fault codes are cleared, or LMUs added/edited recheck for remaining fault codes.
7) Resolved issue where mid-pack contactor failure not detected in multi-string.
8) Removed duplication of temperatures across cell voltages and report actual temperatures only.
9) Modified system to utilize LRU/Temp Zone averages to calculate SOC and SOH.
10) Changed Max/Min/Average Temps and Max/Min Voltages to utilize standard error results.
11) Changed temperature/voltage error report to utilize standard error results instead of single error.
11) Multi-string reporting of Temp/Voltage utilize standard SENSOR_BAD_VALUE.
12) Resolved Fan2 from using Fan1 configuration parameters.
13) Resolved Warranty Reset All/Single save to Non-Volatile memory.
14) Resolved issues where occasional Non-volatile memory read/writes failed, included retries.
15) Resolved Non-volatile memory descriptor roll-over issue.
16) Resolved issue where not enough Warranty LRUs exist in some configurations, increased to 84.
17) Resolved issue where Warranty LRU Intervals did not get calculated consistently.
18) Resolved issue where SOC initialization starts incorrectly due to errors in initial OCV readings.
19) Resolved when larger number of LRUs used not all Warranty calculations are performed.
20) Resolved issue where Warranty Vmin was not being correctly updated after reset.
21) Updated default Configuration descriptions and values.
22) Resolved issue where SOC calculations not performed when missing temperatures.
23) Resolved potential divide by zero issues in validation code and improved checks.
24) Resolved issue when BMU Boots it can utilizes the incorrect CAN Address (single/multi-string).
25) Resolved issue where not using all 3 pins for multi-string address can result in wrong address.