TReX User Manual v2.14 Firmware
Input Handling
Note:
Please refer to
Input Output Hardware Connection
section on this manual for
examples of how to connect the input and output pins on the TReX board.
The TReX supports 8 programmable inputs. Each input can be programmed with a short
message up to 50 characters in length.
Input messages must always be formatted as WT
Protocol
.
On start-up each input is read. By default only inputs that change from the start-up input state
are processed. The expected initial state of each input can be configured, so that on start the
input is not in its expected state there can be an immediate transmission.
Commands relating to input handling (if preferred, all input options can be configured through
the menu system):
*IN_INIT
specifies the expected level on start.
*IN_CONFIG_H
specifies all input transition to high level configuration parameters.
*IN_CONFIG_L
specifies all input transition to low level configuration parameters.
*IN_MSG_H
specifies the high level message that will be transmitted if configured.
*IN_MSG_L
specifies the low level message that will be transmitted if configured.
The *IN_CONFIG_H and *IN_CONFIG_L commands allow the input to specify:
•
How many messages are transmitted once triggered.
•
The debounce period (how long the input must be in a new state continuously in order
to transmit) before the input is triggered.
•
How long to wait until the message is retransmitted.
The *IN_MSG_H and *IN_MSG_L commands allow the input to specify the message which
will be transmitted when the input is triggered.
Full example:
In this example both inputs are configured to transmit only when moving from high to low (no
high level transmissions). Transmit 5 times, 10 seconds between each transmission. Debounce
period is to be configured to 2 seconds (input must have transitioned from a stable low level to
constant high level for two whole seconds).
The protocol being used is WT protocol, and the message for each input message is “IN 1
LOW” and “IN 2 LOW”. Message is to be transmitted as POCSAG alphanumeric to cap code
1234560, beep level 1 and 512 baud.
Both Input 1 and 2 configured to disable all high level processing.
*IN_CONFIG_H=1:0,0,0<CR>
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