Measurement Computing Personal488 rev.3.0 For DOS & Windows 3.Xi User Manual
Page 143
8P. Command Descriptions
II. SOFTWARE GUIDES - 8. Driver488/DRV
II-128
Personal488 User’s Manual, Rev. 3.0
Interrupts
•
interrupt
: One of the following:
SRQ
,
ERROR
,
PERIPHERAL
,
CONTROLLER
,
TRIGGER
,
CLEAR
,
TALK
,
LISTEN
,
IDLE
,
BYTEIN
,
BYTEOUT
,
CHANGE
.
•
[,interrupt...]
: An optional list of interrupts, each preceded by a comma.
Memory Buffer Addresses
•
segment
: A
segment
address in the range
-32768
to
65535
(
&H0
to
&HFFFF
). An address of
the form
segment:offset
is converted into a real 20-bit address by multiplying the
segment
by
16 and adding the
offset
. As the
segment
is often stored in an integer variable, values greater
than
32767
(
32768
to
65535
) are printed as negative numbers (
-32768
to
-1
, respectively).
Driver488/DRV automatically interprets negative
segment
values as their corresponding positive
values.
•
offset
: The
offset
part of a
segment:offset
address. An integer in the range
-32768
to
65535
. As with
segment
, negative offset values are interpreted as their corresponding positive
values.
•
absolute
: A real 20-bit address. An integer in the range
0
to
1,048,575
(
&H0
to
&HFFFFF
).
•
buf-addr
: The memory address of the current data buffer. The
buf-addr
may be given either
as
segment:offset
(the colon is required), or as an
absolute
memory address.
Response
The Response section of the system command description describes the response that the user’s
program should read after sending the command. If a response is provided, it must be read. Errors
occur if another command is issued before reading the response.
Mode
This section of the command description format specifies the operating modes in which the command is
valid. Driver488/DRV may be configured as the System Controller in which case it is initially the
Active Controller, or as a Not System Controller in which case it is initially in the Peripheral state. The
Driver488/DRV configuration as System Controller or Not System Controller can be changed by the
INSTALL
program.
Note:
Even if Driver488/DRV is not configured as the System Controller, it can still become the
Active Controller if another controller on the IEEE 488 bus passes control to Driver488/DRV.
The modes are referred to by their names and states, as shown below:
Mode Name
State
Mode Name
State
System Controller
SC
Not System Controller
*SC
Active Controller
CA
Peripheral
(Not Active Controller)
*CA
Active System Controller
SC
•CA
System Controller, Not Active
SC
•*CA
Not System Controller,
Active Controller
*SC
•CA
Not System Controller,
Not Active Controller
*SC
•*CA
Bus States
This section of the command description format indicates the state of the bus device. The mnemonics
abbreviations for these bus states, as well as the relevant bus lines and bus commands, are listed in the
following two tables: