Measurement Computing Personal488 rev.3.0 For DOS & Windows 3.Xi - Manual (Page 310)

III. COMMAND REFERENCES - 15. Command References 15A. Driver488/DRV Commands
Personal488 User’s Manual, Rev. 3.0 III-295
The IO ADDRESS command specifies the I/O port base address of the I/O adapter. The base address is
set by a sixteen-bit integer, ioaddr , that is usually given as a hexadecimal number. For example, to
use the default I/O address, the command would be IO ADDRESS &H02E1 .
The default I/O port base address for the IEEE 488 hardware interface is &H02E1 for the first interface,
&H22E1 for the second, &H42E1 for the third, and &H62E1 for the fourth interface. The default I/O
port base addresses for the serial hardware interface is &H03F8 . Other standard I/O port base addresses
are &H02F8 , &H03E8 , &H02E8 . The IO ADDRESS value must match the hardware switch settings on
the I/O adapter.
IOCTL (BASIC Statement)
SYNTAX IOCTL#2,"BREAK"
RESPONSE None
MODE Any
BUS STATES None
SEE ALSO IOCTL$
EXAMPLE IOCTL#2,"BREAK" Send the IOCTL message “BREAK” to the Driver488
The IOCTL command is a BASIC statement that can be used to reset Driver488 unconditionally. When
the message “BREAK” is sent to Driver488 via the IOCTL Write DOS function ( &H4403 , accessible
via the IOCTL BASIC statement), Driver488 stops any command currently executing, and prepares to
accept a new command. This can be used even when Driver488 is not expecting a command, but is
transferring data. Commands such as
ABORT or RESET may then be used to reset the entire IEEE 488
bus.
IOCTL resets the EOL OUT terminators to their default values to guarantee that Driver488 is able to
recognize the next command correctly. No IOCTL commands other than BREAK are supported by
Driver488. The IOCTL command can be accomplished in other languages by using MS-DOS function
calls.
IOCTL$ (BASIC Statement)
SYNTAX A$=IOCTL$(#2)
A$ is a string variable that is set to one of the following:
0 if there is nothing to read,
1 if there is something to read,
2 if data should be written,
3 if the remainder of a command is expected.
RESPONSE None
MODE Any
BUS STATES None
SEE ALSO IOCTL
EXAMPLE 100 PRINT#1,"ENTER16"
110 A$=IOCTL$(#2)
120 IF A$="1" THEN PRINT INPUT$(1,#2): GOTO 110
130 PRINT “NO INPUT READY”
The IOCTL$ command is a BASIC statement that can be used to determine the communication state of
Driver488. When data is read from Driver488 using the IOCTL Read DOS command ( &H4402 , access
via the IOCTL$ BASIC function), Driver488 returns a single ASCII character, either 0 , 1 , 2 , or 3 . The
meaning of these responses is:
•
0 : A response of 0 indicates that Driver488 is ready to receive a command. It has no data to read,
nor is it expecting data for output to the IEEE 488 bus.