Casio CTK6000 - Manual (Page 41)

22.2.2 Example: Data send to Instrument from external device
Data Sender Data Receiver Operation
(External Device) (This Instrument)
SBS(OBS) -----> Session Start
Request
Interval *Note
OBS -----> Send Packet (Start
Sub Session)
Interval *Note
OBS -----> Send Packet
Interval *Note
OBS -----> Send Packet
Interval *Note
:
Send Other Packet
:
ESS ----->
<----- ACK End Sub Session
:
Other Sub Session
:
EBS -----> End of Session
Note : The interval is no less than Oneway Min Interval and less than Oneway Max Interval, which are explained under
“24.2 System Exclusive Protocol Parameter”. If the interval exceeds these values, the partner device will issue a timeout error.
22.3 Handshake Mode Communication Flow
22.3.1 Session Start
A single session starts when an external device, which wants to start communication for sending or
receiving data using handshake protocol, sends an SBS (Start of Bulk Dump Session) message to this
Instrument, which is its communication partner. The external device cannot send an HBS or HBR until
this Instrument receives ACK.
22.3.2 Message Timeout Processing
Failure of the next message expected for receipt to arrive within a preset amount of time is viewed as a
timeout error, and ERR (Data = Time Out Error) is sent to the partner device, which then returns to
the message standby state. The device that received the ERR sends the message it believes the partner
device that is in the message receive standby state. If the desired message does not arrive after a preset
number of retries, RJC is sent and the session is terminated. The standby time and number of retries
are determined in accordance with the parameters described under “24.2 System Exclusive Protocol
Parameter”.
22.3.3 Message Format Error Processing
The message receive device returns ERR (Format Error) if it discovers an illegal format in the received
message. When the message sending device receives ERR (Format Error) from the receiving device,
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