HP Saw E4419B manual TTL Input Timing Diagram, Timing of zero/cal inputs for conditions 01

Power Meter Operation

Zeroing and Calibrating the Power Meter

Effective control of the zero and calibration cycles using the TTL inputs depends on correct timing of the input signals as shown in Table 2-3 and Table 2-4.

Table 2-3: TTL Input Timing Diagram 1

Timing of zero/cal inputs for conditions “01” and “10”.

Input

Operation

T1

T2

T3

T4

Time	Description	Value
T1	Minimum width of input	300 ms
T2	Time between input detection and start of zero/cal	Max: 50 ms (typical)
	cycle. This is determined by the number of	Min: 0 ms
	averages x sample rate, or if there is an existing
	zero/cal operation in progress, the time for this
	current operation to complete. Note that the
	worst case is 1024 averages x 50 ms = 51.2 s. For
	front panel operation (in free run mode) the time
	is 1 x 50 ms.
T3	Maximum width of input. Longer inputs may	4 s
	cause a subsequent zero/cal operation some time
	after the current one is complete.
T4	Time for zero/cal operation to complete.	Zero Both: 10 s (each
		8480 series sensor), 12 s
		(each E series sensor)
		Cal: 6 s (8480 series)
		7 s (E series)

All timings based on 100 ms firmware polling.

2-14 HP E4419B User’s Guide