ICS ELECTRONICS 4809A, Instruction Manual

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A-14
A
is active. The last item is 32 (ESR register bit 5) which means execution
error - caused by the BIT 6 command.
A1.3.3 Variables and Channel Lists
SCPI variables are separated by a space from the last keyword in the SCPI
command. The variables can be numeric values, boolean values or ASCII
strings. Numeric values are typically decimal numbers unless otherwise
stated. When setting or querying register values, the decimal variable rep-
resents the sum of the binary bit weights for the bits with a logic '1' value.
e.g. a decimal value of 23 represents 16 + 4 + 2 + 1 or 0001 0111 in binary.
Boolean values can be either 0 or 1 or else OFF or ON. ASCII strings can
be any legal ASCII character between 0 and 255 decimal except for 10
which is the Linefeed character.
Channel lists are used as a way of listing multiple values. Channel lists are
enclosed in parenthesis and start with the ASCII '@' character. The values
are separated with commas. The length of the channel list is determined by
the unit. A range of values can be indicated by the two end values separated
by a colon. e.g.
(@1,2,3,4) 'lists sequential values
(@ 1:4) 'shows a range of sequential values
(@ 1,5,7,34) 'lists random values
Figure A-6 Channel List Examples
A1.3.4 Error Reporting
SCPI provides a means of reporting errors by responses to the SYST:ERR?
query. If the SCPI error queue is empty, the unit responds with 0, "No
error" message. The error queue is cleared at power turn-on, by a *CLS
command or by reading all current error messages. The error messages
and numbers are defined by the SCPI specification and are the same for all
SCPI devices.
A1.3.5 Additional Information
For more information about SCPI refer to the SCPI Standard or to the SCPI
section in any SCPI compatible instrument manual.