Measurement Computing Personal488 rev.3.0 For DOS & Windows 3.Xi - Manual (Page 324)

III. COMMAND REFERENCES - 15. Command References 15A. Driver488/DRV Commands
Personal488 User’s Manual, Rev. 3.0 III-309
These STATUS items are more-fully described in the following paragraphs:
•
The Operating Mode ( C or P ) indicates whether or not Driver488 is the Active Controller. If
Driver488 passes control to another device, the Operating Mode indicator changes from C to P .
When Driver488 regains control, the indicator is C again. If Driver488 is not the System
Controller, it is initially a Peripheral and thus the indicator is P . It does, of course, become C when
Driver488 receives control from the Active Controller.
•
The System Controller Mode ( S or N ) indicates whether or not Driver488 is the System Controller.
If Driver488 is System Controller, the System Controller Mode indicator is S . If Driver488 is not
System Controller, then the System Controller Mode indicator is N . The System Controller Mode
may be configured from the INSTALL program or with the SYS CONTROLLER command.
•
The Primary Bus Address ( 00 to 30 ) is the IEEE 488 bus device primary address assigned to
Driver488 or the specified device. The Secondary Bus Address ( 00 to 31 ) is the IEEE 488 bus
device secondary address assigned to the specified device. If there is no secondary address, this
field is blank.
•
The Address Change ( 0 or 1 ) indicator is set whenever Driver488 become a Talker, Listener, or
the Active Controller, or when it becomes no longer a Talker, Listener, or the Active Controller. It
is reset when
STATUS is read. The Addressed State ( T , L , or I ) is the current Talker/Listener state
of Driver488. As a Peripheral, Driver488 can check this status to see if it has been addressed to
Talk or addressed to Listen by the Active Controller. In this way, the desired direction of data
transfer can be determined.
•
The ByteIn ( 0 or 1 ) indicator is set when the I/O adapter has received a byte that can be read by an
ENTER command. The ByteOut ( 0 or 1 ) indicator is set when the I/O adapter is ready to output
data. The Service Request ( 0 or 1 ) field, as an Active Controller, reflects the IEEE 488 bus SRQ
line signal. As a peripheral, this status reflects the rsv bit that can be set by the REQUEST
command and is cleared when the Driver488 is Serial Polled ( SPOLL ).
•
The Error Code ( 000 ) indicator appears when no error has occurred. If it is non-zero, then the
Error Message (see below) is appended to the STATUS response. The Error Code is reset to 000
when STATUS is read.
•
The Triggered ( T0 or T1 ) and Cleared ( C0 or C1 ) indicators are set when, as a Peripheral,
Driver488 is triggered or cleared. These two indicators are cleared when STATUS is read. The
Transfer in Progress ( P1 ) indicator is set when a CONTINUE transfer is in progress. The Triggered
and Cleared indicators are not updated while CONTINUE transfers ( P1 ) are in progress.
•
The Error Message is a variable text description of the error status. For more details about the
individual errors, refer to Chapter 19 “Error Messages.”
The standard default setting yields the following power-up status response:
CS21 1 I000 000 T0 C0 P0 OK
where the following indicators describe each component of the Driver488/DRV status:
Indicator Driver488/DRV Status
C It is in the Controller state.
S It is the System Controller.
21 The value of its IEEE 488 bus address.
1 An Address Change has occurred.
I It is Idle (neither a Talker nor a Listener).
0 There is no ByteIn available.
0 It is not ready to send a ByteOut.
0 Service Request (SRQ) is not asserted.
000 There is no outstanding error.
T0 It has not received a bus device TRIGGER command (only applicable in the Peripheral mode).
C0 It has not received a CLEAR command (only applicable in the Peripheral mode).
P0 No CONTINUE transfer is in progress.
OK The error message is “OK”.