Owner's manual

36 Function Block and Operation Theory
4. ADCONV, the conversion signal to initiate a single con-
version, which could be derived from internal counter,
AFI[0] or SSI_ADCONV. Note that this signal is edge-
sensitive. When using AFI[0] as the external ADCONV
source, each rising edge of AFI[0] would bring an effec-
tive conversion signal. Also note that the AFI[0] signal
should be TTL-compatible and the minimum pulse width
is 20ns.
4.5.2 Auxiliary Function Inputs (AFI)
You could use the AFI in applications that take advantage of exter-
nal circuitry to directly control the PXI-2020/2022 series cards. The
AFI includes 2 categories of timing signals: one group is the dedi-
cated input, and the other is the multi-function input.