Paradise Datacom RA 5785, Руководство по эксплуатации

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64 208143 REV - Operations Manual, HPA3, Mini Compact Outdoor SSPA
8.1.2.5 Data Address / Error Status / Local Port Frame Length
This field is a tag extension byte and specifies the first table element of the tagged data. If the
Data Length is more than 1 byte, then all subsequent data fields must be accessed starting
from the specified address. For example, if the requestor wants to access the amplifier’s
unique network address, it should set data tag 0 (System settings tag) and data address 8
(see System Settings Details table). If the following Data Length field is more than 1, then all
subsequent Settings will be accessed after the Unique Network Address.
Important! In the Response Frame Data Address filed replaced with the Error Status informa-
tion. The various error codes are given in Table 8-4 .
8.1.2.6 Data Length
This byte value specifies the number of bytes attached in the Data Filed. For the Get
command, it specifies the number of data bytes that have to be returned by the SSPA unit to
a host PC in the Response frame. For Set commands, the value of this byte specifies the
number of data fields to be accessed starting from the address specified in the Data Address
byte. In general, the Data Length value plus the Data Address must not exceed the maximum
data size particular tag.
8.1.2.7 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. “Get Request” will be rejected if any data is pre-
sent in the Data Field. Generally, the Bad Checksum error code will be added to the response
from the unit. In case the data length is 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).
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 respondent buffer to accept
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 originator frame, but respondent failed to
recognize it. All data aborted.
Table 8-4: Error Status Bytes