NCE Mini-Panel Instruction - page 9
Remember that if any of those higher number inputs are grounded the associated
commands starting at that input number will still be executed (unless memory location
4 is programmed) and run until a termination command is encountered.
Interrupting Wait Commands
Wait commands will loop until the input condition is met. No other operations of the
mini panel will be performed while waiting so the panel will appear dead. It is quite
possible that situations on the layout will occur that upset the flow of your automation
‘program’. Imagine that the program is waiting for a loco to get to a certain block and a
derailment occurs causing the train to stop. The loco is replaced on the track but on a
parallel track resulting in the loco never getting to the block that the program is
expecting to be occupied. The mini panel will wait forever appearing to be
unresponsive. You can utilize an unused input of the mini-panel as an ‘interrupt’ to
break the mini panel out of this wait forever loop and continue normal operations.
Program memory location 5 with the input number you want to use as the interrupt. By
connection a pushbutton to this input you can provide a recovery mechanism without
resetting the entire panel, losing turnout positions, signal aspects or loco function
states.
OPs programming command
OPs mode programming requires 3 steps:
set loco address (long or short)
set CV number
set CV data
When the data is set the programming command will be issued out over the cab bus to
the track. If the loco address has already been set in a previous command that
address will be used. The same applies to the CV number. You can use this to your
advantage to program momentum using the (3 required steps) into a locomotive then
later just programming a new momentum value using only the set CV data command.
Command string terminator
When the mini panel encounters the command 0x00,0x00 it is considered the
command string terminator. Any commands following the terminator in the string will
not be executed.
Input scanning
The inputs of the Mini-panel are scanned in numerical order. Inputs are sampled in
groups of 8 and stored in temporary memory. This group is then scanned for active
inputs. An input at or near ground potential is considered active. When an input is
transitions from open (high due to 5v pull-up resistor) to ground (low) it will trigger
execution of a string of up to four commands associated with that input. Transitions
from low to high are ignored and no action is performed.
The lowest numbered active input of the group of eight is acted upon first. The
command string associated with that input will be executed. Execution of the
command string will continue until a command of 0x00,0x00 is encountered or until 4
commands are executed.
One exception to the four command limit is the “link” command that transfers execution
to another input command string. This allows borrowing the memory location from
other (possibly) unused inputs to create longer strings of commands. The memory
space for the unused input can be used by another command string.
Once a command string has completed execution the next active input will be located
and its command string executed.
After a group of 8 inputs is scanned and any active inputs are serviced the next group
of 8 inputs will be sampled.
Inputs are captured eight at a time and actions generated by those 8 inputs are
completed before capturing the next higher group of eight. If an input of one group of 8
initiates a long string of commands (see linking below) that will take a significant period
Last revised: 22 July 2008 Page 9