Sony BKM-FW50 Service Manual page 32

1. Item errors
An item error occurs when the Item No. or Data of a
request is invalid. The conditions under which each error
occurs are described below.
Invalid Item
When Item No. that is not supported is specified
Invalid Item Request
When Item No. is supported, but Request that is not
supported is requested
Invalid Length
When the Data Length of the specified Item No. is too long
Invalid Data
When the Data of the specified Item No. differs in the
setting range
Short Data
When the length of data differs from the value specified
using Data Length
Not Applicable Item
When an item that is not valid at present is specified
2. Community error
This error occurs when community differs.
3. Request errors
These errors occur when a header or command is invalid.
The conditions under which each error occurs are
described below.
Invalid Version
When the version of a header is other than 2
Invalid Category
When a category differs
Invalid Request
When a request that is not supported is specified
Short Header
When the received data is 1 byte
Short Community
When the received data is 2 to 5 bytes
Short Command
When the received data is 6 to 9 bytes
4. Network error
This error occurs in TCP/IP. The conditions under which
an error occurs are described below.
Timeout
When communication was interrupted halfway
5-8
5. Comm error
This is an error that occurs during communication with the
main control microcomputer of display equipment.
Timeout
When the received data is not sent after data transmission
Check Sum Error
When a check sum error occurs in the main control
microcomputer
Framing Error
When a framing error occurs
Parity Error
When a parity error occurs
Over Run Error
When an overrun error occurs
Other Comm Error
When other errors occur
Unknown Response
When data that cannot be processed is received
6. NVRAM error
Read Error
When the read operation from NVRAM fails
Write Error
When the write operation to NVRAM fails
5-8. BKM-FW50 Dedicated Protocol
5-8-1. Packet Format
Command transmission to BKM-FW50
Enquiry
No. Item Value
1 Header 0x83
2 Category 0xDX
3 Function 0xXX
4 Data1 0xXX
5 Data2 0xFF
6 CheckSum* 0xXX
* Checksum: If the value of a sum total of 1 to 5 exceeds 255 (1 byte), the
data of 1 lower byte is effective.
Remarks
The enquiry of an FWD series
protocol is used.
Command type 1 (Refer to the
category list.)
Command type 2
_
Fixed
Checksum for detection of
data destruction
BKM-FW50