Measurement Computing Personal488 rev.3.0 For DOS & Windows 3.Xi - Manual (Page 351)

15B. Driver488/SUB, W31, W95, & WNT III. COMMAND REFERENCES - 15. Command References
III-336 Personal488 User’s Manual, Rev. 3.0
The OutputX command sends data to an interface or external device. The Remote Enable ( REN ) line is
first asserted if Driver488 is the System Controller and AutoRemote is enabled. Then, if a device
address (with optional secondary address) is specified, Driver488 is addressed to Talk and the specified
device is addressed to Listen. If no address is specified, then Driver488 must already be configured to
send data, either as a result of a preceding
OutputX command, or as the result of a Send command.
Terminators are automatically appended to the output data as specified.
The forceAddr flag is used to specify whether the addressing control bytes are to be issued for each
OutputX command. If the device handle refers to an interface, forceAddr has no effect and
command bytes are not sent. If the device handle refers to an external device and forceAddr is TRUE ,
Driver488 addresses the interface to Talk and the external device to Listen. If forceAddr is FALSE ,
Driver488 compares the current device with the most recently addressed device on that interface. If the
addressing information is the same, no command bytes are sent. If they are different,
OutputX acts as
if the forceAddr flag were TRUE and sends the addressing information.
The terminator is a pointer to a terminator structure that is used to set up the input terminators. This
pointer may be a null pointer, requesting use of the default terminators for the device, or it may point to
a terminator structure requesting no terminators. The
async is a flag that allows asynchronous data
transfer. If this flag is TRUE , the OutputX 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 OutputX
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 Output Functions
Driver488 provides additional Output functions that are short form versions of the OutputX function.
The additional Output functions are: Output , OutputN , OutputMore , and OutputNMore . These
functions are discussed in detail below:
Output
SYNTAX long pascal Output(DevHandleT devHandle,char *data);
REMARKS Output is equivalent to the following call to OutputX :
OutputX(devHandle,data,strlen(data),1,1,0L,0,0L);
The Output function passes the device handle and a pointer to the data buffer to the OutputX
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 TRUE , which causes Driver488 to address
the device if an external device is specified. The default terminators are chosen by specifying a 0
pointer as the terminator parameter. Synchronous transmission is specified by sending 0 for the
async parameter, and the completion status value is ignored by sending a 0 for the compStat pointer.
OutputN
SYNTAX long pascal OutputN(DevHandleT devHandle,char *data,long
count);
REMARKS OutputN is equivalent to the following call to OutputX :
OutputX(devHandle,data,count,0,1,0L,0,0L);
The OutputN function passes the device handle and a pointer to the data buffer to the OutputX
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 0 pointer
as the terminator parameter. Synchronous transmission is specified by sending 0 for the async
parameter, and the completion status value is ignored by sending a 0 for the compStat pointer.
OutputMore
SYNTAX long pascal OutputMore(DevHandleT devHandle, char *data);
REMARKS OutputMore is equivalent to the following call to OutputX :