beautypg.com

1 start of packet, 2 target address, 3 address delimiter – Comtech EF Data MBT-4000B User Manual

Page 56: 4 instruction code

background image

MBT-4000B Multi-band Transceiver System

Revision 1

Serial-based Remote Product Management

MN/MBT4000B.IOM

6–4

6.2.4.1 Start of Packet

Because this is used to provide a reliable indication of the start of packet, these two characters may not appear anywhere else within the

body of the message:


Controller-to-Target: This is ‘less-than’ the character '<' (ASCII code 60).

Target-to-Controller: This is the ‘greater-than’ character '>' (ASCII code 62).

6.2.4.2 Target Address

Up to 9,999 devices can be uniquely addressed. In both EIA-232 and EIA-485 applications, the permissible range of values is 1 to 9999.

The BUC sub-device may also be addressed by appending the corresponding sub-device address. The sub-device address for the BUC is

‘A1’. For example, a mute command addressed to the BUC attached to an MBT-4000B at address 0412 will be: <0412A1/MUT=1{CR}

The format of the response will be: >0412A1/MUT={CR}{LF}

The Controller sends a packet with the address of a Target – the destination of the packet. When the Target responds, the

address used is the same address, to indicate to the Controller the source of the packet. The Controller does not have its own

address.

6.2.4.3 Address Delimiter

This is the ‘forward slash’ character ' / ' (ASCII code 47).

6.2.4.4 Instruction Code

This is a three-character alphabetic sequence that identifies the subject of the message. Wherever possible, the instruction codes have

been chosen to have some significance.

For Example: MUT for MUTe. This aids in the readability of the message, should it be displayed in its raw ASCII form.