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int SM_WriteDigitalOutputs ( SM_HANDLE  handle,
int  start,
int  number,
unsigned char *  values 
)

Writes the state of one or more digital outputs.

Parameters:
[in] handle Valid handle returned by SM_Open().
[in] start Starting output (zero-indexed).
[in] number Quantity of outputs to write.
[in] values Desired output state(s).
Return values:
>=0 Number of bytes successfully written.
-1 Invalid SeaMAX handle.
-2 Modbus: Connection is not established. Check the provided Connection object state.
-3 Modbus: Read error waiting for response. Unkown Modbus exception.
-4 Modbus: Illegal Modbus Function (Modbus Exception 0x01).
-5 Modbus: Illegal Data Address (Modbus Exception 0x02).
-6 Modbus: Illegal Data Value (Modbus Exception 0x03).
-7 Modbus CRC was invalid. Possible communications problem.
-20 SeaDAC Lite: Invalid model number.
-21 SeaDAC Lite: Invalid addressing.
-22 SeaDAC Lite: Error writing to the device.
The desired output state(s) parameter ('values') should be an array of bytes, where each byte represents 8 output states. The LSB of the first byte (values[0]) should contain the first 8 output states and should be ordered from LSB to MSB.

For instance, a write of 18 outputs should be an array of 2 bytes as such:

        values[0] = Outputs 7 to 0 (MSB to LSB)
        values[1] = 6 padded bits followed by outputs 17 - 16.
    

 
 
Generated on 18 Sep 2007.