PARALLEL_1284_COMMAND structure (parallel.h)

Article
04/01/2021

The PARALLEL_1284_COMMAND structure specifies information that a client uses to select and deselect an IEEE 1284.3 daisy-chain device or an IEEE 1284 end-of-chain device.

Syntax

typedef struct _PARALLEL_1284_COMMAND {
  UCHAR ID;
  UCHAR Port;
  ULONG CommandFlags;
} PARALLEL_1284_COMMAND, *PPARALLEL_1284_COMMAND;

Members

ID

Specifies the IEEE 1284.3 device ID.

Port

Reserved (set to zero).

CommandFlags

Specifies a bitwise OR of zero or more of the following flags:

PAR_END_OF_CHAIN_DEVICE

Specifies an end-of-chain device.

PAR_HAVE_PORT_KEEP_PORT

Specifies that the client has the parallel port allocated, and makes a request to keep the port allocated.

Remarks

The system-supplied function driver for parallel ports supports the simultaneous connection of zero to two IEEE 1284.3 daisy-chain devices and an IEEE 1284 end-of-chain device. In Windows XP, the parallel port function driver supports the simultaneous connection of zero to four IEEE 1284.3 daisy-chain devices and an IEEE 1284 end-of-chain device. The end-of-chain device must be an IEEE 1284 device, but does not have to be an IEEE 1284.3 device.

For more information, see Selecting and Deselecting an IEEE 1284 Device Attached to a ParallelPort.

Requirements

Requirement	Value
Header	parallel.h (include Parallel.h)