Perform units translation of variables and place the result into variables which will be used for engine control by the ‘ctrl_task’ and compute acceleration rate of engine speed (dndt).

This process is normally started from the ‘go.scp’ startup script and is usually run as a critical task which will cause a watchdog shutdown if it fails. It should be launched after the ‘ctrl_task’.

Run this process at the same process interval as the fastest control loop. Typically, the Dyno and Throttle control loops should be run at FAS or WARP (for CVS cells). The Dyno and Throttle loops should always be run at the same rate and that rate must be included the process interval of this application (comp_ctrl).


comp_ctrl <priority> [+c] &



Specify the task system priority.


Optional. Specify this flag to indicate a critical task.


comp_ctrl 18 +c &


This process will determine its own process interval based on the intervals specified for the dyno and throttle controllers.

This process performs the following functions:

1) Based on the function codes specified in the /specs/spcl_chans.NNN file, it will fetch the following variables, perform units translation and place the result into variables which will be used for engine control by the ‘ctrl_task’.

function_code target_location description

CTRL_ENGINE_RPM ctl_spd engine speed feedback variable

CTRL_DYNO_TORQUE ctl_torq dyno torque feedback variable

DN/DT dndt rate of change of engine speed

2) Compute acceleration rate of engine speed (dndt) is computed unless it is specified as a directly measured variable by the DN/DT function_code in spcl_chans.NNN

gross and net engine torque Gross_torq Net_torq

instantaneous power and bmep Dyno_power BMEP

See Also: