Seaward ClareHAL - Manual (Page 139)

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4. General Protocol Commands
SSSCMD_SESSION_START (command code 0x10)
The “session start” command must be issued before any other protocol
commands. This command is used to:
• Ascertain that the host and tester SSSCMD protocol
implementation
• versions are compatible.
• Specify the baud rate for subsequent command exchanges.
• Supply any password that may be required for subsequent
operations.
It is possible to send a session start command at any time – for
example if a new baud-rate is required, or if password protection is to
be temporarily enabled and then cancelled, or if the tester was left with
a previous session still running. However, it is recommended that under
normal circumstances, when a host has finished with a tester, that the
host should send a session end command to ensure that any password
protection is cancelled and that the tester drops back to 9600 baud.
The data associated with the session start command is as follows:
typedef struct _ssscmddata_session_start {
u8 protocol_ver;
u8 baud_code;
u8 password_seed;
u8 password[ARRAYSZ_SSS_PASSWORD];
} ssscmddata_session_start;
If the ‘itemd id’, ‘instance’, or amount of supplied data is incorrect, then
the tester will respond with SSSRSP_NAK and the appropriate reason
code.
protocol_ver
This describes the SSS CMD protocol version implemented by the
host. Currently any value other than 0 will cause the command to be
rejected with SSSRSP_NAK with the reason code set to
SSSNAK_INVALID_VALUE.
Your HAL tester