SRS Labs QMS 100 Series, Руководство пользователя

Страница: 131 / 280

Communication Errors 3-7
Technical Reference
Communication Errors
Communication errors are signaled to the user flashing the Error LED a few times, setting Bit 0 of the
STATUS error byte and setting the error-specific bits of the RS232_ERR error byte .
Many different circumstances can result in a communication error being reported after a command string
is received by the RGA. Some problems are detected early by the command handler and result in the
command never being executed. Other errors are found later, during the actual command execution, and
they result in the execution being immediately halted.
The following is a list of the communication errors that might be encountered during the analysis and
execution of a command, including the specific ways in which they are reported:
Command errors
Bad Command Name : The first two characters in a command string must be letters (case insensitive)
and must be part of the Command Set, otherwise the Error LED is flashed, Bit 0 of RS232_ERR and
Bit 0 of STATUS are set, and no command is executed.
Command-too-long error : 14 characters are received over RS232 without a <CR> ever being
detected. The Receive buffer is flushed, Bit 2 of RS232_ERR and Bit 0 of STATUS are set, and no
command is executed.
Note that the LED is not flashed for this error (only exception to the rule!) .
Parameter errors
Bad-Parameter error : Many different possibilities lead to a bad-parameter error.
•
The number parameter is out of the command's acceptable range.
•
A “?” is not strictly followed by <CR> in a Query command.
•
A “*” is not strictly followed by <CR> in a Default command.
•
A non-zero fractional part is found in a parameter that can only be an integer.
•
No parameter is found in a command that strictly requires one.
•
A parameter other than a “?” is found in a Query-only command.
•
A default parameter value is used with a command that does not have one defined.
All Bad-Parameter errors are reported flashing the Error LED, and setting Bit 1 of RS232_ERR and Bit
0 of STATUS. No command is executed.
Parameter-conflict error : When the parameter is in conflict with some other related parameter value
which pre-existed in the RGA ECU, the Error LED is flashed, Bit 6 of RS232_ERR and Bit 0 of
STATUS are set and the command is not executed.