VXI VT1538A user manual chlist specifies the channels that will read pulse widths

read pulse widths from CVT

start algorithm

Figure 12. Measure Pulse Width

read puls width on chs 46&47 Algorithm reads the pulse widths on channels 146 and 147 and returns these values in CVT elements 46 and 47

ALG:DEF ’ALG1’,’writecvt( I146, 46 ); writecvt( I147, 47 );’

INIT

. . .

SENS:DATA:CVT? (@46,47)

*RST

SENS:FUNC:PWID 4,(@146,147)

To measure pulse width on channels 46&47

Measure Pulse Width This means that the E1538 will measure the width of the logic 1 portion of a pulse. The pulse width is sent to the algorithm in units of seconds. To measure the high portion of a pulse (positive going edge to negative going edge) set the channel input polarity to INP:POL NORM,(@<ch_list>). To measure the low portion of the pulse (negative going edge to positive going edge) set the channel input polarity to INP:POL INV,(@<ch_list>).

The value returned to an algorithm can be from 5μSec to 1 Second with 59.6nSec resolution.

To configure channels to measure pulse width use the command [SENSe:]:FUNCtion:PWIDth <avg_count>,(@<ch_list>)

•<avg_count> sets the number of pulses to average when forming the pulse duration value. More counts give more accurate readings, but slower response to changing pulse widths.

•<ch_list> specifies the channels that will read pulse widths

20 Agilent E1538A Enhanced Frequency/Totalize/PWM SCP