Man L23/30DF, Project Manual

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The master transmits an inquiry to the slave (CMS) to read a number (n) of
datawords from a given address. The slave (CMS) replies with the required
number (n) of datawords. To read a single register (n) must be set to 1. To
read block type register (n)
must be in the range 1...32.
Request (master):
[DATA] = [ADR][n]
[ADR]=Word stating the address in HEX.
[n]=Word stating the number of words to be read.
Answer (slave-CMS):
[DATA] = [bb][1. word][2. word]....[n. word]
[bb]=Byte, stating number of subsequent bytes.
[1. word]=1. dataword
[2. word]=2. dataword
[n. word]=No n. dataword
The master sends data to the slave (CMS/DM) starting from a particular ad-
dress. The slave (CMS/DM) returns the written number of bytes, plus echoes
the address.
Write data (master):
[DATA] = [ADR][n] [bb][1. word][2. word]....[n word]
[ADR] = Word that gives the address in HEX.
[n] = Word indicating number of words to be written.
[bb] = Byte that gives the number of bytes to follow (2*n)
Please note that 8bb9 is byte size!
[1. word]=1. dataword
[2. word]=2. dataword
[n. word]=No n. dataword
Answer (slave-CMS/DM):
[DATA] = [ADR][bb*2]
[ADR]= Word HEX that gives the address in HEX
[bb*2]=Number of words written.
[1. word]=1. dataword
[2. word]=2. dataword
[n. word]=No n. dataword
FCT = 03H: Read n words
FCT = 10H: Write n words