Comtec MBT-4000, Installation And Operation Manual

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MBT-4000 Multi-Band Transceiver System
Revision 6
Remote Control A–3 MN/MBT4000.IOM
A.5.1 Start of Packet
Controller-to-Target: This is the character ' < ' (ASCII code 60)
Target-to-Controller: This is the character ' > ' (ASCII code 62)
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.
A.5.2 Target Address
Up to 9,999 devices can be uniquely addressed. In both RS-232 and RS-485 applications, the
permissible range of values is 1 to 9999. It is programmed into a target unit using the remote
control port.
The BDC and BUC subdevices may also be addressed by appending the corresponding subdevice
address. The subdevice address is ‘A1’ for the BUC and ‘A2’ for the BDC. For example, a mute
command addressed to a BUC attached to an MBT-4000 at address 0412 will be:
<0412A1/MUT=1{CR}
The format of the response will be:
>0412A1/MUT={CR}{LF}
Subdevice addresses cannot be changed.
IMPORTANT
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.
A.5.3 Address Delimiter
This is the ‘forward slash’ character ' / ' (ASCII code 47).
A.5.4 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. This aids in the
readability of the message if seen in its raw ASCII form. Upper and lower case alphabetic
characters (i.e., A-Z – ASCII codes 65-90, and a-z – ASCII codes 97-122) may be used.