Bird Technologies 4421 - Manual (Page 32)

Bird 4421 RF Power Meter
20
Prefixes (Px)
Function Turns the prefix mode on or off. Set x to:
z “Y” to enable prefixes.
z “N” to disable prefixes.
Remarks Prefixes are sent over the bus with the measurement, and indicate the status
of the current measurement (see Table 5-10 for examples):
z “FC”,”FD”,”RC”,”RD”,”SW”,”RL”,”MN”,”MX” indicates the measure-
ment type.
z “U” indicates underflow; the value sent is “.000”.
z “O” indicates overflow; the value sent is “199.9”.
z “N” indicates normal; the value sent is a normal on-scale reading.
z “4421” indicates the Bird model number.
Table 5-10 Prefix Examples
Triggers (Tx)
Function Selects the condition which will trigger a reading (see Table 5-11).
Remarks Failure to trigger device before requesting a reading will lock the bus.
T1 halts the bus until a reading is available.
T0 and T1 do not set the measurement complete SRQ.
T2, T3, T4, and T5 set a SRQ when the measurement is complete.
Fastest reading rate is 2.4 readings/second; slowest is 1 reading/sec.
Table 5-11 Trigger Conditions
Data String Description
NFC.0.123W(CR)(LF)
Normal (N) forward carrier wave (FC), prefixes on
OFC 199.9W(CR)(LF)
Overflowed (O) forward carrier wave (FC), prefixes on
199.9W(CR)(LF)
Overflowed forward carrier wave, prefixes off
URD .000W(CR)(LF)
Underflowed (U) reflected dBm (RD), prefixes on
Command Trigger Condition
T0 Continuous on talk
T1 One shot on talk
T2 Continuous on GET
T3 One shot on GET
T4 Continuous on measurement command (FC,FD,
RC, RD, SW, RL, MN, MX)
T5 One shot on measurement command (FC, FD,
RC, RD, SW, RL, MN, MX)