Reads the entire I/O space of a Sealevel programmable IO device.
- Parameters
-
| [in] | handle | Valid handle returned by SM_Open(). |
| [out] | values | After completion, contains the state of the Sealevel I/O device's inputs and outputs. |
- Return values
-
| >0 | Successful completion. Number of bytes of valid data in pioValues. |
| -1 | Invalid SeaMAX handle. |
| -2 | Connection is not established. Check the provided Connection object state. |
| -3 | Read error waiting for response. Unknown Modbus exception. |
| -4 | Illegal Modbus Function (Modbus Exception 0x01). |
| -5 | Illegal Data Address (Modbus Exception 0x02). |
| -6 | Illegal Data Value (Modbus Exception 0x03). |
| -7 | Modbus CRC was invalid. Possible communications problem. |
| -10 | SeaDAC Lite: Invalid model number. |
| -11 | SeaDAC Lite: Unknown connection type. |
| -12 | SeaDAC Lite: Error communicating with device. |
This method attempts to read the state of the programmable IO for any applicable Sealevel I/O module. The data is returned as a packed array of bytes reflecting the state of ports A1 to C4, MSB to LSB. For instance, a 96-bit PIO module would return 12 bytes of packed data as such:
values[0] = Port A1 (PIO 7 to 0 - MSB to LSB)
values[1] = Port B1 (PIO 15 to 8)
values[2] = Port C1 ...
values[3] = Port A2
values[4] = Port B2
...
values[11] = Port C4
- Warning
- The parameter, values, must have at least one bytes of space allocated for each bank of 8 I/O points before calling this function. For instance, a SeaDAC Lite module with 32 PIO would require 4 bytes of pre-allocated space.
Referenced by CSeaMaxW32::Read().
