Lantronix XPort - Manual (Page 51)

GPIO Interface
Command 10h, Get Functions
Send:
No
parameters
Response:
1
parameter
Bytes 1-4: Functions
Bit X 1 means general purpose IO available to the user.
0 means dedicated function (e.g., serial flow control, diagnostics) for
configurable pin X.
Command 11h, Get Directions
Send:
No
parameters
Response:
1
parameter
Bytes 1-4: Directions
Bit X 1 means GPIO X is an output.
0 means it is an input.
Command 12h, Get Active Levels
Send:
No
parameters
Response:
1
parameter
Bytes 1-4: Active levels
Bit X 1 means GPIO X is active low (0V when active, 3.3V when inactive).
0 means it is active high (3.3V when active, 0V when inactive).
Command 13h, Get Current States
Send:
No
parameters
Response:
1
parameter
Bytes 1-4: States
Bit X 1 means GPIO X is active
0 means it is inactive.
XPort™ User Guide 5-3