Measurement Computing Personal488 rev.3.0 For DOS & Windows 3.Xi - Manual (Page 359)

15B. Driver488/SUB, W31, W95, & WNT III. COMMAND REFERENCES - 15. Command References
III-344 Personal488 User’s Manual, Rev. 3.0
The RemoveDevice command removes the specific temporary or permanent Driver488 device that
was created with either the MakeDevice command or the startup configuration. This command also
removes a device that was made permanent through a KeepDevice command.
Request
SYNTAX int pascal Request(DevHandleT devHandle, int spstatus);
devHandle refers to either an interface or an external device. If devHandle
refers to an external device, the Request command acts on the hardware
interface to which the external device is attached.
spstatus is the Service Request status in the range 0 to 255 .
RETURNS -1 if error
MODE *CA
BUS STATES SRQ if rsv is set, *SRQ if not.
SEE ALSO Status, ControlLine
EXAMPLES errorcode = Request(ieee,0) Clear SRQ and Serial Poll Response.
errorcode =
Request(ieee,64+2+4)
Generate an SRQ (decimal 64) with DIO2
(decimal 2) and DIO3 (decimal 4) set
in the serial poll response.
In Peripheral mode, Driver488 is able to request service from the Active Controller by asserting the
Service Request (
SRQ ) bus signal. The Request command sets or clears the Serial Poll status
(including Service Request) of Driver488. Request takes a numeric argument in the decimal range
0 to 255 (hex range &H0 to &HFF ) that is used to set the Serial Poll status. When Driver488 is Serial
Polled by the Controller, it returns this byte on the DIO data lines.
The data lines are numbered DIO8 through DIO1 . DIO8 is the most significant line and corresponds to
a decimal value of 128 (hex &H80 ). DIO7 is the next most significant line and corresponds to a
decimal value of 64 (hex &H40 ). DIO7 has a special meaning: It is the Request for Service ( rsv ) bit. If
rsv is set, then Driver488 asserts the Service Request ( SRQ ) bus signal. If DIO7 is clear (a logic 0 ),
then Driver488 does not assert SRQ. When Driver488 is Serial Polled, all eight bits of the Serial Poll
status are returned to the Controller. The
rsv bit is cleared when Driver488 is Serial Polled by the
Controller. This causes Driver488 to stop asserting SRQ .
Reset
SYNTAX int pascal Reset(DevHandleT devHandle);
devHandle refers to either an interface or an external device. If devHandle
refers to an external device, the Reset command acts on the hardware
interface to which the external device is attached.
RETURNS -1 if error
MODE Any
BUS STATES None
SEE ALSO Abort, Term, TimeOut
EXAMPLE errorcode=Reset(ieee);
The Reset command provides a warm start of the interface. It is equivalent to issuing the following
command process, including clearing all error conditions:
1. Stop
2. Disarm
3. Reset hardware. (Resets to Peripheral if not System Controller)
4. Abort (if System Controller)
5. Error ON
6. Local
7. Request 0 (if Peripheral)