Priority; Details Of Each Frame And Priority; Result Only Mode - Hitachi 902 Service Manual

16.4.5 Priority

When multiple processings concur in response to a request from the host, the analyzer assigns
priority to them for returning its response to the host.
However, batch communication is suspended in units of text for transferring to the host the text
which has a higher priority than batch communication when it interrupts batch communication
under execution (restricted to the cases where analytical data in the real-time mode is output
from analyzer and analytical data alone is transferred in response to RES frame).
(Discrimination between real-time communication data and batch communication data depends
on the function frame.)
Then, batch communication is restarted.
Table 16-6 gives the details of each frame and the priority.
Priority
1 Sending of SPE (stat sample)
2 Sending of SPE (routine sample) frame
3 Sending of REP (resending request) frame
4 Sending of analytical data in response to RES from host (transfer of data read from FD)
5 Sending of higher-priority analytical data (transfer of data read from FD)
6 Sending of lower-priority analytical data (analytical data in real-time communication)

16.4.6 RESULT ONLY Mode

In this mode, only the measurement result data is transferred to the host. This mode does not
accept a resending request (REP frame) from the analyzer or host and a specific sample data
request. When [YES] is set for "transfer of analytical data alone" on the communication
parameter screen, the analyzer returns response to neither test selecting inquiry for routine/stat
samples nor specification of test selection from the host.
The analyzer waits for 1 sec or more after sending ETX in the analytical data text and proceeds
to transfer to the host regardless of the communication procedure.
STX
Table 16-6 Details of Each Frame and Priority
1 sec or more
Transfer
sequence
Text ETX BCC
Item
Text: Analytical data text
STX Text ETX
16 - 17
BCC