Keysight VXI Bus 75000 C Series User And Programming Manual page 14

Getting Started
SCPI commands provided for the digital I/O module allow operation in 8-bit
"BYTE" format, 16-bit "WORD" format (using two ports), 32-bit "LWORd" format
(using four ports), 64-bit "LW64" format (using eight ports), and 96-bit "LW96"
format (using all ports).
Figure 1-1 Keysight E1458A Digital I/O Module
12 Keysight E1458A 96-Channel Digital I/O Module User Guide
Digital I/O Module Description