FLT

Requests/sets all LM628 filter values (proportional, integral, derivative, integration limit, and derivative sampling interval) with one command[11].

Mnemonic:

FiLTers

Syntax:

FLT $<$n$>$[, $<$kp, ki, kd, il, dsi$>$]

n: Axis number (0:azimuth, 1:elevation).

kp: Proportional value (0 - 32767)

ki: Integral value (0 - 32767)

kd: Derivative value (0 - 32767)

il: Integration limit value (0 - 32767)

dsi: Derivative sampling interval value (0 - 255)

Return values:

Success:

FKP 1, n, kp, ki, kd, il, dsi

Failure:

FKP 0[, n], err_msg

n: Axis number.

kp: New or current proportional value.

ki: New or current integral value.

kd: New or current derivative value.

il: New or current integration limit value.

dsi: New or current derivative sampling interval value.

err_msg: Should the command fail, this value will be an error message string, explaining the cause of failure. FLT may fail for any of the following reasons:

• The wrong number of parameters were supplied.
• A non-numeric value is provided for any of the parameters.
• The axis number in n is not `0' or `1'.
• One or more of the filter parameters contains a number that is outside the valid range for the PID filter (the command will fail at the first non-numeric parameter encountered).

Remarks:

FLT is useful when all LM628 filter parameters must be set, allowing them to be all set by one command. The LM628 PID filters must be properly tuned for the servo systems to work properly. For a detailed discussion on tuning the LM628 PID filter, see ``LM628 Programming Guide (National Semiconductor Application Note 693)''[12]

Example:

     send: FLT 1, 200, 300, 3500, 20, 1
  receive: FLT 1, 1, 200, 300, 3500, 20, 1

     send: FLT 1
  receive: FLT 1, 1, 200, 300, 3500, 20, 1

See also:

FIL, FKD, FKI, FKP, FSI