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XAGN — Acceleration Thresholds (Under Development)

This message is used to configure positive and negative acceleration limits (thresholds). Acceleration thresholds are monitored with the N signals:

Note: That for positive acceleration thresholds, Acceleration Signals are TRUE when the vehicle's acceleration is larger than the threshold. For negative acceleration thresholds, Acceleration Signals are TRUE when the vehicle's acceleration is less than the threshold.

Signals

SignalDescription
N00N04Active when measured acceleration meets the configured signed threshold

Signal behavior:

  • Positive threshold: signal activates when acceleration ≥ threshold (rapid speed increase).
  • Negative threshold: signal activates when acceleration ≤ threshold (rapid deceleration / braking).

Command Format

Query — QXAGN

>QXAGN{NN}<

Where {NN} is the slot index (0004).

Response when configured:

>RXAGN{NN}1{SIGN}{VV}<

Response when not configured:

>RXAGN{NN}U<

Where:

  • {NN} — slot index (0004)
  • {SIGN}+ for positive (acceleration), - for negative (deceleration)
  • {VV} — threshold value in mph/s, 2 digits zero-padded (0199)

Set — SXAGN

>SXAGN{NN}1{SIGN}{VV}<

Delete — SXAGN{NN}U

>SXAGN{NN}U<

Clears slot {NN} and deasserts its signal.

Parameters

FieldValuesDescription
NN0004Slot index
SIGN+ or -Direction of acceleration
VV0199Threshold magnitude in mph/s
note

Value 00 is rejected — a threshold of zero has no physical meaning.

Examples

Set slot N00 to trigger on acceleration ≥ 13 mph/s (hard acceleration):

>SXAGN001+13<
>RXAGN<

Set slot N01 to trigger on deceleration ≤ −10 mph/s (hard braking):

>SXAGN011-10<
>RXAGN<

Query slot N00:

>QXAGN00<
>RXAGN001+13<

Query unset slot N02:

>QXAGN02<
>RXAGN02U<

Delete slot N01:

>SXAGN01U<
>RXAGN<