Paradise 205486 REV F Remote Control Interface, Serial Communication Protocol, Header Packet

Section 10: Remote Control Interface

10.0 Serial Communication Protocol

This section describes the basic serial communication protocol between the Compact Outdoor SSPA and a host computer. Serial port settings must be configured for 8 bit data at no parity, with 1 stop bit.

The Amplifier will only respond to properly formatted protocol packets. The basic communica- tion packet is shown in Figure 10-1. It consists of a Header, Data, and Trailer sub-packet.

HEADER	DATA	TRAILER
(4 bytes)	(6-32 bytes)	(1 byte)

Figure 10-1: Basic Communication Packet

10.1 Header Packet

The Header packet is divided into 3 sub-packets which are the Frame Sync, Destination Address, and Source Address packets, as shown in Figure 10-2.

HEADER (4 bytes)

DATA

(6-32 bytes)

TRAILER

(1 byte)

Frame Sync (2 bytes)

0xAA5

Destination Address

(1 byte)

Source Address

(1 byte)

Figure 10-2: Header Sub-Packet

10.1.1 Frame Sync Word

The Frame Sync word is a two byte field that marks the beginning of a packet. This value is always 0xAA55. This field provides a means of designating a specific amplifier packet from others that may exist on the same network. It also provides a mechanism for a node to syn- chronize to a known point of transmission.

10.1.2 Destination Address

The destination address field specifies the node for which the packet is intended. It may be an individual or broadcast address. The broadcast address is 0xFF. This is used when a packet of information is intended for several nodes on the network. The broadcast address can be used in a single device connection when the host needs to determine the address of the amplifier. The Compact Outdoor amplifier will reply with its unique address.

Operations Manual, HPA2, Compact Outdoor SSPA 205486 REV F 87