Seaward ClareHAL - Manual (Page 141)

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password
If the host is supplying a password, then ‘password_seed’ must be
non-zero, and the supplied password must be scrambled using the
combination of the CRC lookup tables and the defined seed value. This
allows passwords to be exchanged without them being readable on
RS232 data loggers etc. It also allows the password to be supplied
‘differently’ each time – if, for example, a non-zero random number is
used as the seed.
The function ‘sss_start_session()’ within the example software
demonstrates how to scramble a password.
SSSCMD_SESSION_END (command code 0x11)
It is recommended, but not essential, to send a session end command
after the host has finished with a tester. This ensures that any
password protection is cancelled and that the tester drops back to
9600 baud. This makes is quicker to start the next session as the host
can then always expect to send the initial session start request at 9600
baud.
If the ‘itemd id’, ‘instance’, or amount of supplied data is non-zero, then
the tester will respond with SSSRSP_NAK and the appropriate reason
code.
SSSCMD_NOP (command code 0x12)
This allows the host to solicit an ACK without performing any action.
The example software uses SSSCMD_NOP as a confidence test after
starting a session – primarily to check that the session baud rate is
correct. Other host systems may wish to use SSSCMD_NOP to
periodically ascertain that a session is still ‘alive’ if no other commands
have been issued for a period of time.
If the ‘itemd id’, ‘instance’, or amount of supplied data is non-zero, then
the tester will respond with SSSRSP_NAK and the appropriate reason
code.
SSSCMD_CLEAR_SCREEN (command code 0x13)
This command turns off the tester’s buzzer, and completely clears the
tester’s display. This may be useful if the default session message is
not required.
Your HAL tester