INT32S DRV_DioReadDIPorts( PTR_T DeviceHandle, INT32U dwPortStart, INT32U dwPortCount, INT8U *pBuffer );
On the device indicated by the DeviceHandle, it reads back the DI port data from a specified range of DI ports.
Some parameters, such as starting port number (dwPortStart), port count (dwPortCount) and pointer to the user's buffer (pBuffer), are stored in the DRV_DioReadDIPorts.
The user needs to provide a buffer that is large enough to store retrieved data.
| Name | Direction | Range | Description |
| DeviceHandle | input | default | The pointer retrieved from the DRV_DeviceOpen which specifies the target device. |
| dwPortStart | input | default | The starting port number. |
| dwPortCount | input | default | The port count. |
| pBuffer | output | default | The pointer to the user's buffer that saves DI data. |
| 1. 0 | Successful. |
| 2. InvalidDeviceHandle | The DeviceHandle is NULL. |
| 3. InvalidChannel | The port is configured incorrectly. The start port number (dwPortStart) or the sum of the start number and the port count (dwPortCount) should not exceed the total DI port number. |
| 4. InvalidBuffer | The user's buffer is configured incorrectly. It should not be NULL. |