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Command #09 - DirectionACmd
Description:
Set the i⁄o direction of port A.
Command Format:
| Byte Number | Description |
| 0 | 09h: DirectionACmd |
| 1 | direction0 The most significant bit of the byte value is associated with A.7 |
| 2 | direction1 The most significant bit of the byte value is associated with A.7 |
| 3 | <not used> |
| 4 | <not used> |
| 5 | <not used> |
| 6 | <not used> |
| 7 | <not used> |
Command Format Details:
Byte 0 contains the command. Byte 1 is written to the direction0 control register, byte 2 is written to the direction1 control register appropriate for this port. Byte 3 through byte 7 are unused.
The individual pins of the ports can be set to input, or output. Input is set when both bits associated with a particular line are set to 0. There are different types of outputs available for the board, but generally setting both of the direction bits to 1 will suffice.
Response Format:
| Byte Number | Description |
| 0 | 09h: DirectionACmd |
| 1 | <not used> |
| 2 | <not used> |
| 3 | <not used> |
| 4 | <not used> |
| 5 | <not used> |
| 6 | <not used> |
| 7 | <not used> |
Response Format Details:
Byte 0 contains the command. Byte 1 through byte 7 are unused.
Example Usage:
The command 09-00-00-00-00-00-00-00 will set the port to all input, the command 09-FF-FF-00-00-00-00-00 will set the port to all output. To have the upper nibble be input and the lower nibble output, use the command 09-0F-0F-00-00-00-00-00.
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