Marantz SR7002 - Manual (Page 6)

SR8002/SR7002
RS-232C Control Specification
Page: 6 / 32
Document Version [1.00]
Company Restricted
3-2. Transmission data format
3-2-1. Transmission data format from Host to Slave
There are two kinds of transmission data form from Host shown below.
3-2-1-1. Form1: Command
Command is a data that requests some status change.
Start character : ’@’
COMMAND : see “Command list”
End character (CR) : 0Dh
Start
@
Command
“xxx:”+”...”
End
0Dh
3-2-1-2. Form2: Status request
Status request is a data that requests a answer of some status.
Start character : ’@’
Request status : see “Status request list”
Request character : ‘?’
End character (CR) : 0Dh
Start
@
Command
“xxx:?”+”...”
End
0Dh
3-2-2. Transmission data format from Slave to Host
There are two kinds of transmission data form from Slave shown below.
3-2-2-1. Form1: ACK/NAK
ACK is a reply data from Slave when Slave got an acceptable command data from Host.
(ACK is sent to Host when Slave has no related status by the Command.)
Start character : ’@’, ACK : 06h, End character (CR) : 0Dh
Start
@
ACK
06h
End
0Dh
NAK is a reply data from Slave when Slave got an incorrect Command data, Status request data or
some other data from Host.
Start character : ’@’, NAK : 15h, End character (CR) : 0Dh
Start
@
NAK
15h
End
0Dh
3-2-2-2. Form2: Status answer and Auto status feedback
Status answers are reply data when Slave got an acceptable Request status or Command data from
Host. Auto status feedbacks are send to Host data when a Slave’s status is changed.
Start character : ’@’
Answer character : see “Status list”
End character (CR) : 0Dh
Start
@
Status
“xxx:”+”...”
End
0Dh