IQH1S 1U Enclosure
SECTION 3
IQH1SOPS
23/11/06
www.snellwilcox.com
Version 1 Issue 4
3.8
RS485 Differential Interface
This interface allows bus connections to internal pieces of equipment such as front panels. It is a multi-drop
differential bus with a data rate of 2.5 Mb/s. The data format used on this bus is identical to that used on the
coaxial network, hence can provide a natural hub between coaxial sections.
Example configuration:
RS422 Asynchronous Interface
This interface is specifically designed for third party connections into the system and runs at 38.4 Kb/s.
This allows PC's or any other serial device access to any of the units within the system. Every active 1U or 3U
box has one of these ports. The port operates in binary mode: formatted packet data is sent to the port using
STX and ETX characters.
Example configuration:
A serial device attached to a single IQ rack has access to
all
devices on the RollCall network.