Online Development Notebook > Index > Programming Overview > Device Commands > InitPorts (and variations)

InitPorts (and variations) - Initialize device, ports

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Description:

This is a function that initializes both ports, and resets the device's internal latches.

There are two 8-bit ports on the U401⁄421⁄U451, 16 I⁄O lines. The 16 total I⁄O lines can be set to inputs or outputs on an individual per-line basis. The initial state of the ports on power up is that all of the 16 lines are set to be inputs.

Command Syntax: (USBm.dll)

USBm_InitPorts( device )

The USBm_InitPorts function syntax has these parts:

Remarks:

Calling USBm_InitPorts will reset the ports to input and will clear the internal latches.

Calling USBm_InitPortsU401 will reset the ports to input and will clear the internal latches.

Calling USBm_InitPortsU421 will reset the ports to input and will clear the internal latches.

Calling USBm_InitPortsU451 will reset port A to input, port B to output and will clear the internal latches.

There is nothing stopping you from calling the USBm_InitPortsU421 when connected to a U401, for instance. Or any of the other combinations. The different flavors of init are provided for user convenience. USBm_InitPortsU451 is currently the only different one in the group as it sets port B to all output.

USBm_InitPorts is in all versions of the DLL. The variations are present in version 65 or newer.

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VB Declaration

Public Declare Function USBm_InitPorts _     Lib "USBm.dll" _         (ByVal device As Byte) _    As Integer Public Declare Function USBm_InitPortsU401 _     Lib "USBm.dll" _         (ByVal device As Byte) _    As Integer Public Declare Function USBm_InitPortsU421 _     Lib "USBm.dll" _         (ByVal device As Byte) _    As Integer Public Declare Function USBm_InitPortsU451 _     Lib "USBm.dll" _         (ByVal device As Byte) _    As Integer

VB Example

USBm_InitPorts (3)

This code fragment initializes the ports of device number three.

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C Prototype

int USBm_InitPorts( unsigned char device ); int USBm_InitPortsU401( unsigned char device ); int USBm_InitPortsU421( unsigned char device ); int USBm_InitPortsU451( unsigned char device );

C Example

USBm_InitPorts( 0 );

This code fragment initializes the ports of device number 0 (the first U4x1 device that is found).

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RobotBASIC

usbm_InitPorts(ne_DeviceNumber)

Returns true if successful, false otherwise. This function resets the A and B ports as Input Ports, which is the default state upon connecting the device to the PC.

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Raw Command Format:

Raw Command Format Details:

Byte 0 contains the command. Byte 1 through byte 7 are unused.

Raw Command Response Format:

Raw Command Response Format Details:

Byte 0 contains the command. Byte 1 through byte 7 are unused.

Raw Command Example Usage:

Sending the InitPortsCmd command to the device will reset the ports.

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Hardware:  U401 USB Interface    U421 USB Interface   U451 USB Interface

Programming:  USBm DLL Programming    Download Files

Application Notes:  U4x1 Application Notes    Misc Applications and Information    FAQ

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