Accessing a Card - Card Numbers and Sub-Unit Numbers

Card Numbers

Once a session has been opened onto a chassis, be it LXI or PXI, it is necessary to Open a specific switch card in the chassis.

Two functions are provided, when opened by PIPLX_OpenCards, each Pickering card is accessed using a logical card number, starting from 1.
 

When opened by PIPLX_OpenSpecifiedCard, the logical card number associated with a card (its "handle") is the value returned in the CardNum argument.

When a card is no longer needed it is closed using PIPLX_CloseSpecifiedCard, or all cards may be closed using PIPLX_CloseCards

Sub-Unit Numbers

All Pickering cards contain one or more independently addressable functional blocks, or sub-units. Sub-unit numbers begin at 1, and separate sequences are used for input and output functions. This number is used in function calls to access the appropriate block. Generally, sub-unit numbers correspond directly to the bank numbers specified in hardware documentation.

Sub-unit examples:

Model	Configuration	INPUT sub-unit #1	OUTPUT sub-unit #1	OUTPUT sub-unit #2	OUTPUT sub-unit #3
40-110-021	16 SPDT switches	None	16 SPDT switches	None	None
40-290-121	Dual Programmable resistors + 16 SPDT switches	None	Resistor #1	Resistor #2	16 SPDT switches
40-490-001	Digital I/O	16-channel inputs	32-channel outputs	None	None
40-511-021	Dual 12 x 4 matrix	None	12 x 4 matrix #1	12 x 4 matrix #2	None