From Agilent Multimeter Wiki

STAT?

Returns overall meter status

Effect

none

Response

"000001I00210L00104001"

• 1st digit: Average function 0=OFF 1=ON
• 2nd digit: Null function 0=OFF 1=ON
• 3rd digit: dB Function 0=OFF V=dBV M=dBM
• 4th digit: Change terminal 0=normal 1=alert
• 5th digit: Peak hold function 0=OFF 1=ON (PEAK button)
• 6th digit: Current percent 0=0-20mA 1=4-20mA
• 7th digit: "I" UNKNOWN
• 8th digit: Refresh hold function 0=OFF 1=ON (HOLD button)
• 9th digit: Zero temperature compensation 0=OFF 1=ON
• 10th digit: Beep selection 0=OFF C=300Hz F=600Hz 1=1200Hz 2=2400Hz
• 11th digit: Auto power off 0=OFF 1=ON
• 12th digit: Backlight 0=OFF 1=ON
• 13th digit: "L" UNKNOWN
• 14th digit: "0" UNKNOWN
• 15th digit: Amps terminal plug 0=Disconnected 1=Connected
• 16th digit: Rotary position (0-8 for U1252A, 0-7 for U1251A)
  • 0=ACV, 1=V, 2=mV, 3=Res, 4=Diode, 5=Cap, 6=uA, 7= mA/A, 8=Square Wave (only U1252A)
• 17th digit: Output status 0=standby 1=operation (only U1252A)
• 18th digit: "4" UNKNOWN
• 19th digit: "0" UNKNOWN
• 20th digit: "0" UNKNOWN
• 21th digit: AutoRange 0=OFF 1=ON
• quotes included

Candidates for the UNKNOWN digits: battery level, fc derived path, input warning, meter mode, rate count, trigger source (the ones not identified from agilent gui properties tab).