Preliminary User Guide, Rev. 2

USS-720

February 1999

USB Device Driver

 

 

4 I/O Control Codes

This section provides information for the I/O control codes used in the DeviceIoControl file function (see

Section 3.4). These control codes are used in the DeviceIoControl function to perform any of the following device- specific operations.

Note: Refer to the header file <USS720io.h> included on the USS-720 Evaluation Kit diskette for details regarding these control codes definitions. Please note that this file may be subject to periodic modifications. To obtain more information about these control codes, contact In-System Design.

Control Code

Description

 

 

IOCTL_1284_ ECP_FWDTOREV

Negotiates the peripheral from forward idle to reverse while in

 

ECP register mode.

 

 

IOCTL_1284_ECP_REVTOFWD

Negotiates the peripheral from reverse to forward idle while in

 

ECP register mode.

 

 

IOCTL_1284_ ECP_SET_CHANNEL

Sets the ECP channel on the peripheral for reads and writes.

 

 

IOCTL_1284_ SET_MODE

Negotiates the peripheral into one of the valid register modes.

 

 

IOCTL_1284_ TERMINATE

Performs a standard 1284 termination sequence.

 

 

IOCTL_ABORT_PIPE

Cancels any pending transfers for the specified pipe. The pipe

 

state and endpoint state are unaffected.

 

 

IOCTL_CANCEL_PIPE_REQUEST

Cancels the current request on the specified pipe by flushing

 

the pipe and canceling any outstanding requests on that pipe.

 

 

IOCTL_GET_ALTSETTING

Retrieves the current alternate interface setting from the USS-

 

720 device.

 

 

IOCTL _GET_CAPABILITIES

Returns a variable buffer length containing the device capabil-

 

ities string. This is a IEEE 1284 compatible string.

 

 

IOCTL_GET_CONFIGURATION_DESCRIPTOR

Retrieves the current configuration descriptor.

 

 

IOCTL_GET_DEVICE_DESCRIPTOR

Receives the current device descriptor.

 

 

IOCTL_GET_DEVICE_INSTANCES

Returns a list of current devices based on the symbolic links

 

created during each device enumeration.

 

 

IOCTL_GET_INTERFACE

Gets the information about the current interface and pipes.

 

 

IOCTL _GET_PORT_STATUS

Returns a status byte.

 

 

IOCTL_ISSUE_USS720_COMMAND

Issues a specific command for the USS-720 device.

 

 

IOCTL _GET_1284_REGISTER

Returns all 1284 registers.

 

 

IOCTL_READ_INTERRUPT_PIPE

Reports changes in the parallel port and buffer status when

 

they occur.

 

 

IOCTL_RESET_PIPE

Clears the halted state of the specified pipe within the USB

 

stack and resets the stalled state of the endpoint on the

 

device.

 

 

IOCTL _SET_1284_REGISTER

Sets one of the 1284 registers.

 

 

IOCTL _SET_ALTSETTING

Sets the alternate interface setting.

 

 

IOCTL _SOFT_RESET

Resets the device, flushes the Bulk Out and Bulk In pipes to

 

the default states.

 

 

Lucent Technologies Inc.

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Lucent Technologies USS-720 manual O Control Codes, Control Code Description