Lucent Technologies USS-720 manual IOCTL1284ECPREVTOFWD, 4 I/O Control Codes continued, February

Preliminary User Guide, Rev. 2	USS-720
February 1999	USB Device Driver

4 I/O Control Codes (continued)

4.2 IOCTL_1284_ECP_REVTOFWD

IOCTL_1284_ECP_REVTOFWD negotiates the peripheral from reverse to forward idle while in ECP register mode. Details regarding parameters and error codes follow.

4.2.1 Parameters

lpInBuffer—Points to an input buffer. Not used with this operation. Set to NULL.

nInBufferSize—Specifies the size (in bytes) of the buffer pointed to by lpInBuffer. Not used with this operation. Set to zero.

lpOutBuffer—Points to an output buffer. Not used with this operation. Set to NULL.

nOutBufferSize—Specifies the size (in bytes) of the buffer pointed to by lpOutBuffer. Not used with this operation. Set to zero.

lpBytesReturned—Points to a DWORD that receives the actual size (in bytes) of the data stored into lpOutBuffer. Not used with this operation.

4.2.2 Notes

Requires that the register-based mode be successfully set to ECP_REGISTER_MODE or

ECP_RLE_REGISTER_MODE (see USS-720USB-to-IEEE 1284 Bridge Preliminary Data Sheet, “Register-Based Operation” and Section 4.4, IOCTL_1284_SET_MODE, of this document).

4.2.3 Error Codes

ERROR_INVALID_ALTERNATESETTING—This command is only supported in ALT_INTERFACE_2 (see Section 4.9).

STATUS_IO_DEVICE_ERROR—Negotiation failed.

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