Rice Lake CW-90X Over/Under/Washdown Checkweigher - Lantronix MatchPort - Manual (Page 71)

MatchPort b/g™ User Guide 71
6 6 : : C C o o n n f f i i g g u u r r a a b b l l e e P P i i n n s s
The MatchPort has eight pins configurable for General Purpose I/O (GPIO).
Use these GPIO pins to control devices such as relays, servers, lights, monitor
switches, sensors, and even processes such as data transfer.
Defaults Settings
 Function: general purpose input/output
 Direction: input
 Active Level: low
Set the functions for the eight pins independently and in any combination. The initial
directions (input/output) and active levels (low or high active) at boot up can also be
configured through 77FE.
This chapter describes how the directions, active levels, and states can be
dynamically controlled and probed through special port 77F0.
Features
 TCP and UDP can be used.
 The protocol supports up to 32 GPIO for future products.
 Function configuration can be retrieved.
 Input or output selection can be retrieved and controlled.
 Active low or high selection can be retrieved and controlled.
 Active or inactive selection can be retrieved and controlled.
 77F0 can be disabled.
Every change of state (active/inactive) requires a command over TCP or UDP, and
thus is not very fast. If you use this port for data transfer, the throughput is low,
usually up to 1 Kbps.
Control Protocol
The GPIO control protocol, a simple, proprietary protocol, is described below.
Guidelines
The GPIO control protocol is described from the PC side. Send means from PC to
MatchPort. Response comes from MatchPort to PC.
The protocol allows for control of up to 8 GPIOs.
The parameters are four bytes long and represent GPIOs 0-31, with GPIO0 in bit 0 of
the first byte (Little Endian). Parameter bits for configurable pins not configured as
GPIOs are undefined for Get commands and ignored on Set commands.
Every command consists of nine bytes: one command type of one byte and two
parameters of four bytes each.