RCP2-1000 RM Remote Controller Operations Manual
203987 Rev A
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5.1.2.6 Data Length
This byte contains different information for Request and Response frames. In a Re-
quest frame, it specifies the number of data bytes that are to be accessed starting from
the first byte of the value specified in the Data Address byte. That byte must not ex-
ceed the maximum data bytes from a particular tag. The maximum data length for the
Settings tag is 26 bytes. The maximum data length for the System Threshold tag is six
(6) bytes.
5.1.2.7 Data Field
The actual data contained in the packet must be placed in this field. The “Get Request”
type of command must not contain any Data Field. Any “Get Request” will be rejected if
any data is present in the Data Field. Generally, the Bad Checksum error code will be
added to the response from the amplifier if the word size of the information is 16-bits or
2-bytes. Each data word is placed in the frame with its least significant byte first. All
data with length of 2 bytes must be represented as integer type with maximum value
range from 32767 to (-32767).
5.1.3 Trailer Packet
The trailer component contains only one (1) byte called the Frame Check Sequence
(See Figure 5-4).
Error Code
name
Byte
Value
Possible Cause
No Errors
0
Normal Condition, no errors detected
Data Frame Too
Big
1
Specified Data length is to big for RCP2 buffer to ac-
cept
No Such Data
2
Specified Data Address is out off bounds for this tag
data
Bad Value
3
Specified value not suitable for this particular data type
Read Only
4
Originator tried to set a value which has read only
status
Bad Checksum
5
Trailer checksum not matched to calculated checksum
Unrecognizable
error
6
Error presented in incoming framed, but RCP unit failed
to recognize it. All data aborted.
Table 5-3: Error Status Bytes
