Hardware Features
MN1258V4 08/2000
31
Communications
During reset CAN controller will have no effect on the CAN bus. If a
reset
occurs during the
transmission of a message CAN errors are likely to occur.
When the controller goes into a reset state all serial communications will be terminated immediately,
this may result in incomplete or corrupted messages.
Digital Outputs
All of the digital outputs are inactive on power up regardless of their polarity. They will return to the
inactive state whenever
reset
occurs.
Analog Outputs
All analog outputs are set to 0V by hardware during power-up and will return to 0V on a
reset
.
However the output buffer circuit may have a small offset and so the actual voltage seen at the output
may not be zero.
3.10
Battery Backup of Memory
The RAM is backed up with a battery to prevent loss of data when the main power is removed.
Switching from the main power (V
CC
) to the battery power (V
BAT
) is done by the reset chip when
V
CC
falls below V
BAT
. The power consumption of this switch is 1µA maximum at room
temperature.
The backup battery is a 3 cell nickel metal hydride (NiMH) with a nominal voltage of 3.6V
(1.2V/cell) and a capacity of 280mAh. A standard low power 0.5Mbyte SIMM requires
approximately 1.2µA at 3.0V for data retention. This, coupled with the consumption of the battery
switch, gives a total consumption of 2.2µA. Theoretically this would give a data retention time of
14 years. However, the self discharge characteristics of the battery mean that it will drop to 60%
charge in 6 months at 20°C. Memory contents will be retained down to 95% discharge which takes
approximately 3 years. This self discharge is faster at higher temperatures, at 45°C the battery will
drop to approximately 45% charge in 1 month giving a data retention time of only 4 months. Should
the battery become very discharged, it is recommended that it be removed and fully recharged
outside the unit since its maximum capacity will have been reduced to about 80% of nominal.
3.10.1 Changing the Battery
Access to the battery is gained by removing the 2 screws at the bottom of the rear vertical extrusion
and the opposing screws at the top of the extrusion. The extrusion and the side plate can then be
removed giving access to the PCB. Once the PCB is exposed the battery can be removed by cutting
the restraining cable tie and disconnecting it from the main board. Replacement batteries and cable
ties can be obtained from.
When the battery is disconnected the program and other data held in RAM may be corrupted or lost.
It is therefore advisable to back up all data on the controller before changing the battery.
Never attempt to open the unit while it is powered.
Summary of Contents for NextMove BX
Page 1: ...MN1258V4 08 2000 NextMove BX Installation Manual for Mint v4 Issue 4 0...
Page 2: ...NextMove BX Installation Manual for Mint v4 ii MN1258V4 08 2000...
Page 4: ...NextMove BX Installation Manual for Mint v4 iv MN1258V4 08 2000...
Page 8: ...NextMove BX Installation Manual for Mint v4 viii MN1258V4 08 2000...
Page 12: ...NextMove BX Installation Manual for Mint v4 xii MN1258V4 08 2000...
Page 18: ...NextMove BX Installation Manual for Mint v4 6 MN1258V4 08 2000...
Page 22: ...NextMove BX Installation Manual for Mint v4 10 MN1258V4 08 2000 Figure 3 3 Board Settings...
Page 46: ...NextMove BX Installation Manual for Mint v4 34 MN1258V4 08 2000...
Page 78: ...NextMove BX Installation Manual 66 MN1258V4 08 2000...
Page 82: ...NextMove BX Installation Manual 70 MN1258V4 08 2000...
Page 88: ...NextMove BX Installation Manual 76 MN1258V4 08 2000...
Page 92: ...NextMove BX Installation Manual 80 MN1258V4 08 2000...
Page 94: ...NextMove BX Installation Manual 82 MN1258V4 08 2000...