Effect Of Cycling Bcu Power - Trane Tracer Summit Hardware And Software Installation Manual

Table 41. LED Sequences When BCU is Receiving Code
Red Green
On Flashing
Flashing Off
Flashing Flashing
BMTW-SVN01F-EN
Startup and Troubleshooting Sequence for the BCU (BMTS)
CR16 CR17
When the BCU receives its first block of code from the PC
Off On
Workstation, the green LED will turn on for several seconds,
and then flash rapidly for several seconds. This indicates that
the BCU is erasing the Flash EPROM chips into which the code
will be burned. Three separate on/flicker sequences can be
observed—one per Flash EPROM chip. If a chip cannot be
erased, then the BCU will flash the red and green LEDs alter-
nately as described above.
Off On Once the BCU has erased Flash EPROM, the red LED will
flicker or flash as the BCU requests and receives additional
blocks of code from the PC Workstation and burns them into
Flash EPROM. If a chip cannot be programmed, then the BCU
will flash the red and green LEDs alternately as described
above.
Off On If the device ID DIP switches are all on when the final block of
BCU.IMG has been burned, the BCU will flash the red and
green LEDs together, several times per second. This is a nor-
mal condition. It serves as a warning that the BCU cannot
enter normal operation with the DIP switches all on. It will
persist until the BCU is turned off, the DIP switch changed,
and power is restored.

Effect of Cycling BCU Power

The effect of cycling power on the BCU is different than on other Trane
products such as the Tracer 100. Actions are as follows:
1. When power is restored, the BCU will go through the power up
sequence described above. In particular, it will verify that the main
code BCU.IMG is intact.
2. If the BCU determines that a complete power failure interrupt
sequence occurred, and that RAM is intact, then the contents of RAM
will be preserved. This includes the states of control vectors, trend
logs, and similar historical values. If the specified conditions are not
met, RAM will be cleared.
3. If an Ethernet card, ARCNET card, EIA-232 card, or modem has been
installed or removed during the power failure, RAM will be cleared.
4. All UCMs are scanned in order to acquire current input data.
5. Analog and Binary Input scan is enabled. Since the UCMs have
already been scanned, the values referenced by the Input Objects will
be current.
6. Certain special CPL routines execute in order to perform reset pro-
cessing. Applications may request outputs, but no outputs to UCMs
are actually performed.
Explanation
231