T.E.M. A07B500S, Manual

Page: 59 / 131

A07B500S manual
Pag. 59
REMOTE CONTROL
SERIAL COMMUNICATION PROTOCOL
8.1
Communication between TX and Personal Computer has been issued by means of
standard serial port RS232 and RS485. Software running on P.C. and firmware built-in TX
microprocessor, transfer data using EBU Universal Encoder Communication Protocol, version 4.0
(EBU UECP).
EBU UECP Standards are:
a) 1 start bit, 8 data bit, 1 stop bit, no parity.
b) Transmission speeds must be one of the following standard values: 75,150,300,600,1200,2400,
4800,9600,19200,38400,57600,115200 bps. Our choice is 2400 bps.
c) General Frame Format:
STA
ADDh ADDl SQC MFL MSG
0
MSG
1
… … ... MSG
255
CRCh CRCl STP
STA… … … . Start Byte (FE hex)
ADDh… … .. Address MSB (user set)
ADDl … … ...Address LSB (user set)
SQC … … … .Sequence Counter (frame counter)
MFL … … … Message Field Length (N° of message bytes (0-255) prior to byte-stuffing)
MSG … … … Message (Any value in the range 00-FF hex)
CRCh .… ....Cyclic Redundancy Check MSB (Error check using 16-bit CRC calculation)
CRCl … ...… Cyclic Redundancy Check LSB
STP … … … ..Stop Byte (FF hex)
d) Byte-Stuffing
Byte values FD, FE and FF hex are trapped in the fields “ADD” to “CRC” and transformed
into pair of bytes as shown in following table:
Byte
Resultant byte pair
FD
FE
FF
Transformed into FD 00
FD 01
FD 02
CRC is applied to bytes ADDh,ADDl,SQC,MFL,MSG.. before byte-