Measurement Computing Personal488 rev.3.0 For DOS & Windows 3.Xi User Manual

Page 354

III. COMMAND REFERENCES - 15. Command References

15B. Driver488/SUB, W31, W95, & WNT

Personal488 User’s Manual, Rev. 3.0

III-339

a terminator structure requesting no terminators. The

async%

is a flag that allows asynchronous data

transfer. If this flag is

TRUE

, the

OutputXI

command returns to the caller as soon as the data transfer

is underway and can be completed under DMA and/or interrupts.

FALSE

indicates that the

OutputXI

command should not return until the transfer is complete. The

compStat%

is a pointer to an integer

containing completion status information. A null pointer indicates that completion status is not
requested. In the case of an asynchronous transfer, this pointer must remain valid until the transfer is
complete.

Additional OutputI Functions

Driver488 provides additional

OutputI

functions that are short form versions of the

OutputXI

function. The additional

OutputI

functions are:

OutputNI

OutputMoreI

, and

OutputNMoreI

These functions are discussed in detail below:

OutputNI

SYNTAX

OutputNI(ByVal devHandle%, data%, ByVal count&) As Long

REMARKS

OutputNI

is equivalent to the following call to

OutputXI

OutputXI(devHandle%,data%,count&,0,1,0,0,0)

The

OutputNI

function passes the device handle and a pointer to the data buffer, to the

OutputXI

function. It specifies that the

forceAddr%

flag is set

TRUE

, which causes Driver488 to address the

device if an external device is specified. The default terminators are chosen by specifying a

pointer

as the

terms

parameter. Synchronous transmission is specified by sending

for the

async

parameter,

and the completion status value is ignored by sending a

for the

compStat

pointer.

OutputMoreI

SYNTAX

OutputMoreI(ByVal devHandle%,data%,By Val count&)As Long

REMARKS

OutputMoreI

is equivalent to the following call to

OutputXI

OutputXI(devHandle%,data%,count&,1,0,0,0,0)

The

OutputMoreI

function passes the device handle and a pointer to the data buffer, to the

OutputXI

function. It determines the size of the data buffer provided by the user and passes that value as the

count&

parameter. It specifies that the

forceAddr%

flag is set

FALSE

, so Driver488 does not re-

address the device if it is the same device as that previously used. The default terminators are chosen
by specifying a

pointer as the

terms

parameter. Synchronous transmission is specified by sending

for the

async

parameter, and the completion status value is ignored by sending a

pointer for the

compStat

pointer.

OutputNMoreI

SYNTAX

OutputNMoreI(ByVal devHandle, data%, ByVal count&) As Long

REMARKS

OutputNMoreI

is equivalent to the following call to

OutputXI

OutputXI(devHandle%,data%,count&,0,0,0,0,0);

The

OutputNMoreI

function passes the device handle and a pointer to the data buffer, to the

OutputXI

function. It specifies that the

forceAddr%

flag is set

FALSE

, so Driver488 does not re-

address the device if it is the same device as that previously used. The default terminators are chosen
by specifying a

pointer as the

terms

parameter. Synchronous transmission is specified by sending

for the

async

parameter, and the completion status value is ignored by sending a

pointer for the

compStat

pointer.

Note:

The

OutputNI

and

OutputNMoreI

commands do not send terminators. Also,

OutputI

and

OutputMoreI

must be passed to the entire array (i.e.

intarray()

, not the starting location:

intarray (0)

The following table describes the differences between the various forms of

OutputI

. It outlines the

variables passed to each function and how many bytes the functions output.